diff --git a/README.md b/README.md
index 64e71255..6652a14a 100644
--- a/README.md
+++ b/README.md
@@ -24,13 +24,14 @@ Features
 - Support image and PDF files
 - Flexible search engine
 - Full text search in image and PDF
-- SHA-256 encryption
+- 256-bit AES encryption
 - Tag system
 - Multi-users ACL system
 - Audit log
 - Document sharing by URL
 - RESTful Web API
 - Fully featured Android client
+- Tested to 100k documents
 
 Download
 --------
diff --git a/docs-android/app/app.iml b/docs-android/app/app.iml
index d5ce36f5..afd2300c 100644
--- a/docs-android/app/app.iml
+++ b/docs-android/app/app.iml
@@ -12,10 +12,12 @@
         <option name="SELECTED_TEST_ARTIFACT" value="_android_test_" />
         <option name="ASSEMBLE_TASK_NAME" value="assembleDebug" />
         <option name="COMPILE_JAVA_TASK_NAME" value="compileDebugSources" />
-        <option name="SOURCE_GEN_TASK_NAME" value="generateDebugSources" />
         <option name="ASSEMBLE_TEST_TASK_NAME" value="assembleDebugAndroidTest" />
         <option name="COMPILE_JAVA_TEST_TASK_NAME" value="compileDebugAndroidTestSources" />
-        <option name="TEST_SOURCE_GEN_TASK_NAME" value="generateDebugAndroidTestSources" />
+        <afterSyncTasks>
+          <task>generateDebugAndroidTestSources</task>
+          <task>generateDebugSources</task>
+        </afterSyncTasks>
         <option name="ALLOW_USER_CONFIGURATION" value="false" />
         <option name="MANIFEST_FILE_RELATIVE_PATH" value="/src/main/AndroidManifest.xml" />
         <option name="RES_FOLDER_RELATIVE_PATH" value="/src/main/res" />
@@ -24,7 +26,7 @@
       </configuration>
     </facet>
   </component>
-  <component name="NewModuleRootManager" inherit-compiler-output="false">
+  <component name="NewModuleRootManager" LANGUAGE_LEVEL="JDK_1_7" inherit-compiler-output="false">
     <output url="file://$MODULE_DIR$/build/intermediates/classes/debug" />
     <output-test url="file://$MODULE_DIR$/build/intermediates/classes/androidTest/debug" />
     <exclude-output />
@@ -34,13 +36,13 @@
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/buildConfig/debug" isTestSource="false" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/rs/debug" isTestSource="false" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/res/rs/debug" type="java-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/generated/debug" type="java-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/resValues/debug" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/r/androidTest/debug" isTestSource="true" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/aidl/androidTest/debug" isTestSource="true" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/buildConfig/androidTest/debug" isTestSource="true" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/source/rs/androidTest/debug" isTestSource="true" generated="true" />
       <sourceFolder url="file://$MODULE_DIR$/build/generated/res/rs/androidTest/debug" type="java-test-resource" />
-      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/generated/androidTest/debug" type="java-test-resource" />
+      <sourceFolder url="file://$MODULE_DIR$/build/generated/res/resValues/androidTest/debug" type="java-test-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/debug/res" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/debug/resources" type="java-resource" />
       <sourceFolder url="file://$MODULE_DIR$/src/debug/assets" type="java-resource" />
@@ -75,9 +77,9 @@
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/dependency-cache" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/dex" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/dex-cache" />
-      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/com.android.support/appcompat-v7/22.1.1/jars" />
-      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/com.android.support/recyclerview-v7/22.0.0/jars" />
-      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/com.android.support/support-v4/22.1.1/jars" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/com.android.support/appcompat-v7/22.2.1/jars" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/com.android.support/recyclerview-v7/22.2.1/jars" />
+      <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/com.android.support/support-v4/22.2.1/jars" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/com.shamanland/fab/0.0.6/jars" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/it.sephiroth.android.library.easing/android-easing/1.0.3/jars" />
       <excludeFolder url="file://$MODULE_DIR$/build/intermediates/exploded-aar/it.sephiroth.android.library.imagezoom/imagezoom/1.0.5/jars" />
@@ -106,16 +108,16 @@
     </content>
     <orderEntry type="jdk" jdkName="Android API 22 Platform" jdkType="Android SDK" />
     <orderEntry type="sourceFolder" forTests="false" />
-    <orderEntry type="library" exported="" name="appcompat-v7-22.1.1" level="project" />
     <orderEntry type="library" exported="" name="fab-0.0.6" level="project" />
     <orderEntry type="library" exported="" name="android-easing-1.0.3" level="project" />
     <orderEntry type="library" exported="" name="imagezoom-1.0.5" level="project" />
+    <orderEntry type="library" exported="" name="support-v4-22.2.1" level="project" />
     <orderEntry type="library" exported="" name="eventbus-2.4.0" level="project" />
+    <orderEntry type="library" exported="" name="recyclerview-v7-22.2.1" level="project" />
     <orderEntry type="library" exported="" name="android-query.0.26.8" level="project" />
     <orderEntry type="library" exported="" name="tokenautocomplete-1.2.1" level="project" />
-    <orderEntry type="library" exported="" name="support-v4-22.1.1" level="project" />
-    <orderEntry type="library" exported="" name="support-annotations-22.1.1" level="project" />
-    <orderEntry type="library" exported="" name="recyclerview-v7-22.0.0" level="project" />
+    <orderEntry type="library" exported="" name="support-annotations-22.2.1" level="project" />
+    <orderEntry type="library" exported="" name="appcompat-v7-22.2.1" level="project" />
     <orderEntry type="library" exported="" name="android-async-http-1.4.6" level="project" />
   </component>
 </module>
\ No newline at end of file
diff --git a/docs-android/app/build.gradle b/docs-android/app/build.gradle
index c9195ab8..e162b17a 100644
--- a/docs-android/app/build.gradle
+++ b/docs-android/app/build.gradle
@@ -3,7 +3,7 @@ buildscript {
         mavenCentral()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:1.2.3'
+        classpath 'com.android.tools.build:gradle:1.3.0'
     }
 }
 apply plugin: 'com.android.application'
@@ -14,7 +14,7 @@ repositories {
 
 android {
     compileSdkVersion 22
-    buildToolsVersion "22.0.1"
+    buildToolsVersion "23.0.2"
 
     defaultConfig {
         minSdkVersion 14
@@ -50,8 +50,8 @@ android {
 
 dependencies {
     compile fileTree(dir: 'libs', include: '*.jar')
-    compile 'com.android.support:appcompat-v7:22.1.1'
-    compile 'com.android.support:recyclerview-v7:22.0.0'
+    compile 'com.android.support:appcompat-v7:22.+'
+    compile 'com.android.support:recyclerview-v7:22.+'
     compile 'com.loopj.android:android-async-http:1.4.6'
     compile 'it.sephiroth.android.library.imagezoom:imagezoom:1.0.5'
     compile 'de.greenrobot:eventbus:2.4.0'
diff --git a/docs-android/app/src/main/java/com/sismics/docs/activity/DocumentViewActivity.java b/docs-android/app/src/main/java/com/sismics/docs/activity/DocumentViewActivity.java
index 5ecc3dee..ea2e8cbe 100644
--- a/docs-android/app/src/main/java/com/sismics/docs/activity/DocumentViewActivity.java
+++ b/docs-android/app/src/main/java/com/sismics/docs/activity/DocumentViewActivity.java
@@ -168,7 +168,7 @@ public class DocumentViewActivity extends AppCompatActivity {
         createdDateTextView.setText(date);
 
         TextView descriptionTextView = (TextView) findViewById(R.id.descriptionTextView);
-        if (description == null || description.isEmpty()) {
+        if (description == null || description.isEmpty() || description.equals(JSONObject.NULL.toString())) {
             descriptionTextView.setVisibility(View.GONE);
         } else {
             descriptionTextView.setVisibility(View.VISIBLE);
diff --git a/docs-android/app/src/main/java/com/sismics/docs/listener/RecyclerItemClickListener.java b/docs-android/app/src/main/java/com/sismics/docs/listener/RecyclerItemClickListener.java
index 084a20e3..4287396b 100644
--- a/docs-android/app/src/main/java/com/sismics/docs/listener/RecyclerItemClickListener.java
+++ b/docs-android/app/src/main/java/com/sismics/docs/listener/RecyclerItemClickListener.java
@@ -11,7 +11,7 @@ public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListen
   private OnItemClickListener mListener;
 
   public interface OnItemClickListener {
-    public void onItemClick(View view, int position);
+    void onItemClick(View view, int position);
   }
 
   GestureDetector mGestureDetector;
@@ -25,7 +25,8 @@ public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListen
     });
   }
 
-  @Override public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
+  @Override
+  public boolean onInterceptTouchEvent(RecyclerView view, MotionEvent e) {
     View childView = view.findChildViewUnder(e.getX(), e.getY());
     if (childView != null && mListener != null && mGestureDetector.onTouchEvent(e)) {
       mListener.onItemClick(childView, view.getChildPosition(childView));
@@ -33,5 +34,9 @@ public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListen
     return false;
   }
 
-  @Override public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) { }
+  @Override
+  public void onTouchEvent(RecyclerView view, MotionEvent motionEvent) { }
+
+  @Override
+  public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { }
 }
\ No newline at end of file
diff --git a/docs-core/pom.xml b/docs-core/pom.xml
index 69acf4c0..cf4d3719 100644
--- a/docs-core/pom.xml
+++ b/docs-core/pom.xml
@@ -113,6 +113,11 @@
       <artifactId>bcprov-jdk15on</artifactId>
     </dependency>
     
+    <dependency>
+      <groupId>com.levigo.jbig2</groupId>
+      <artifactId>levigo-jbig2-imageio</artifactId>
+    </dependency>
+    
     <!-- OCR dependencies -->
     <dependency>
       <groupId>jna</groupId>
diff --git a/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/TagDao.java b/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/TagDao.java
index da108dd9..dbff4438 100644
--- a/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/TagDao.java
+++ b/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/TagDao.java
@@ -103,7 +103,7 @@ public class TagDao {
     @SuppressWarnings("unchecked")
     public List<TagDto> getByDocumentId(String documentId, String userId) {
         EntityManager em = ThreadLocalContext.get().getEntityManager();
-        StringBuilder sb = new StringBuilder("select t.TAG_ID_C, t.TAG_NAME_C, t.TAG_COLOR_C from T_DOCUMENT_TAG dt ");
+        StringBuilder sb = new StringBuilder("select t.TAG_ID_C, t.TAG_NAME_C, t.TAG_COLOR_C, t.TAG_IDPARENT_C from T_DOCUMENT_TAG dt ");
         sb.append(" join T_TAG t on t.TAG_ID_C = dt.DOT_IDTAG_C ");
         sb.append(" where dt.DOT_IDDOCUMENT_C = :documentId and t.TAG_DELETEDATE_D is null ");
         sb.append(" and t.TAG_IDUSER_C = :userId and dt.DOT_DELETEDATE_D is null ");
@@ -123,6 +123,7 @@ public class TagDao {
             tagDto.setId((String) o[i++]);
             tagDto.setName((String) o[i++]);
             tagDto.setColor((String) o[i++]);
+            tagDto.setParentId((String) o[i++]);
             tagDtoList.add(tagDto);
         }
         return tagDtoList;
@@ -137,7 +138,7 @@ public class TagDao {
     @SuppressWarnings("unchecked")
     public List<TagStatDto> getStats(String userId) {
         EntityManager em = ThreadLocalContext.get().getEntityManager();
-        StringBuilder sb = new StringBuilder("select t.TAG_ID_C, t.TAG_NAME_C, t.TAG_COLOR_C, count(d.DOC_ID_C) ");
+        StringBuilder sb = new StringBuilder("select t.TAG_ID_C, t.TAG_NAME_C, t.TAG_COLOR_C, t.TAG_IDPARENT_C, count(d.DOC_ID_C) ");
         sb.append(" from T_TAG t ");
         sb.append(" left join T_DOCUMENT_TAG dt on t.TAG_ID_C = dt.DOT_IDTAG_C and dt.DOT_DELETEDATE_D is null ");
         sb.append(" left join T_DOCUMENT d on d.DOC_ID_C = dt.DOT_IDDOCUMENT_C and d.DOC_DELETEDATE_D is null and d.DOC_IDUSER_C = :userId ");
@@ -158,6 +159,7 @@ public class TagDao {
             tagDto.setId((String) o[i++]);
             tagDto.setName((String) o[i++]);
             tagDto.setColor((String) o[i++]);
+            tagDto.setParentId((String) o[i++]);
             tagDto.setCount(((Number) o[i++]).intValue());
             tagStatDtoList.add(tagDto);
         }
@@ -281,6 +283,7 @@ public class TagDao {
         // Update the tag
         tagFromDb.setName(tag.getName());
         tagFromDb.setColor(tag.getColor());
+        tagFromDb.setParentId(tag.getParentId());
         
         // Create audit log
         AuditLogUtil.create(tagFromDb, AuditLogType.UPDATE);
diff --git a/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagDto.java b/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagDto.java
index 343acd90..6666015d 100644
--- a/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagDto.java
+++ b/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagDto.java
@@ -23,6 +23,11 @@ public class TagDto {
      * Color.
      */
     private String color;
+    
+    /**
+     * Parent ID.
+     */
+    private String parentId;
 
     /**
      * Getter of id.
@@ -77,4 +82,22 @@ public class TagDto {
     public void setColor(String color) {
         this.color = color;
     }
+    
+    /**
+     * Getter of parentId.
+     *
+     * @return the parentId
+     */
+    public String getParentId() {
+        return parentId;
+    }
+
+    /**
+     * Setter of parentId.
+     *
+     * @param color parentId
+     */
+    public void setParentId(String parentId) {
+        this.parentId = parentId;
+    }
 }
diff --git a/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagStatDto.java b/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagStatDto.java
index cb54a7d7..03b0e76c 100644
--- a/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagStatDto.java
+++ b/docs-core/src/main/java/com/sismics/docs/core/dao/jpa/dto/TagStatDto.java
@@ -2,7 +2,7 @@ package com.sismics.docs.core.dao.jpa.dto;
 
 
 /**
- * Tag DTO.
+ * Tag stat DTO.
  *
  * @author bgamard 
  */
diff --git a/docs-core/src/main/java/com/sismics/docs/core/model/jpa/Tag.java b/docs-core/src/main/java/com/sismics/docs/core/model/jpa/Tag.java
index 70fcba4c..e556c7d2 100644
--- a/docs-core/src/main/java/com/sismics/docs/core/model/jpa/Tag.java
+++ b/docs-core/src/main/java/com/sismics/docs/core/model/jpa/Tag.java
@@ -39,6 +39,12 @@ public class Tag implements Loggable {
     @Column(name = "TAG_IDUSER_C", nullable = false, length = 36)
     private String userId;
     
+    /**
+     * User ID.
+     */
+    @Column(name = "TAG_IDPARENT_C", length = 36)
+    private String parentId;
+    
     /**
      * Creation date.
      */
@@ -165,12 +171,31 @@ public class Tag implements Loggable {
     public void setDeleteDate(Date deleteDate) {
         this.deleteDate = deleteDate;
     }
+    
+    /**
+     * Getter of parentId.
+     *
+     * @return parentId
+     */
+    public String getParentId() {
+        return parentId;
+    }
+
+    /**
+     * Setter of parentId.
+     *
+     * @param parentId parentId
+     */
+    public void setParentId(String parentId) {
+        this.parentId = parentId;
+    }
 
     @Override
     public String toString() {
         return MoreObjects.toStringHelper(this)
                 .add("id", id)
                 .add("name", name)
+                .add("parentId", parentId)
                 .toString();
     }
 
diff --git a/docs-core/src/main/java/com/sismics/docs/core/util/FileUtil.java b/docs-core/src/main/java/com/sismics/docs/core/util/FileUtil.java
index 702160b3..40e04e15 100644
--- a/docs-core/src/main/java/com/sismics/docs/core/util/FileUtil.java
+++ b/docs-core/src/main/java/com/sismics/docs/core/util/FileUtil.java
@@ -105,7 +105,7 @@ public class FileUtil {
         PDDocument pdfDocument = null;
         try {
             PDFTextStripper stripper = new PDFTextStripper();
-            pdfDocument = PDDocument.load(inputStream, true);
+            pdfDocument = PDDocument.load(inputStream);
             content = stripper.getText(pdfDocument);
         } catch (IOException e) {
             log.error("Error while extracting text from the PDF", e);
@@ -157,7 +157,7 @@ public class FileUtil {
             // Generate preview from the first page of the PDF
             PDDocument pdfDocument = null;
             try {
-                pdfDocument = PDDocument.load(inputStream, true);
+                pdfDocument = PDDocument.load(inputStream);
                 PDFRenderer renderer = new PDFRenderer(pdfDocument);
                 image = renderer.renderImage(0);
             } finally {
diff --git a/docs-core/src/main/resources/config.properties b/docs-core/src/main/resources/config.properties
index 9484a82d..d8b90e8b 100644
--- a/docs-core/src/main/resources/config.properties
+++ b/docs-core/src/main/resources/config.properties
@@ -1 +1 @@
-db.version=1
\ No newline at end of file
+db.version=2
\ No newline at end of file
diff --git a/docs-core/src/main/resources/db/update/dbupdate-002-0.sql b/docs-core/src/main/resources/db/update/dbupdate-002-0.sql
new file mode 100644
index 00000000..14551cf3
--- /dev/null
+++ b/docs-core/src/main/resources/db/update/dbupdate-002-0.sql
@@ -0,0 +1,2 @@
+alter table T_TAG add column TAG_IDPARENT_C varchar(36);
+update T_CONFIG set CFG_VALUE_C = '2' where CFG_ID_C = 'DB_VERSION';
diff --git a/docs-parent/pom.xml b/docs-parent/pom.xml
index 44d9d50a..5f3882e1 100644
--- a/docs-parent/pom.xml
+++ b/docs-parent/pom.xml
@@ -35,6 +35,7 @@
     <joda-time.joda-time.version>2.8.2</joda-time.joda-time.version>
     <org.hibernate.hibernate.version>4.1.0.Final</org.hibernate.hibernate.version>
     <javax.servlet.javax.servlet-api.version>3.1.0</javax.servlet.javax.servlet-api.version>
+    <com.levigo.jbig2.levigo-jbig2-imageio.version>1.6.3</com.levigo.jbig2.levigo-jbig2-imageio.version>
 
     <org.eclipse.jetty.jetty-server.version>9.2.13.v20150730</org.eclipse.jetty.jetty-server.version>
     <org.eclipse.jetty.jetty-webapp.version>9.2.13.v20150730</org.eclipse.jetty.jetty-webapp.version>
@@ -66,6 +67,12 @@
         <enabled>true</enabled>
       </snapshots>
     </repository>
+    
+    <repository>
+      <id>jbig2.googlecode</id>
+      <name>JBIG2 ImageIO-Plugin repository at googlecode.com</name>
+      <url>http://jbig2-imageio.googlecode.com/svn/maven-repository</url>
+    </repository>
   </repositories>
   
 
@@ -252,11 +259,11 @@
       </dependency>
       
       <dependency>
-	      <groupId>org.glassfish.jersey.test-framework.providers</groupId>
-	      <artifactId>jersey-test-framework-provider-bundle</artifactId>
-	      <type>pom</type>
-	      <version>${org.glassfish.jersey.version}</version>
-	    </dependency>
+        <groupId>org.glassfish.jersey.test-framework.providers</groupId>
+        <artifactId>jersey-test-framework-provider-bundle</artifactId>
+        <type>pom</type>
+        <version>${org.glassfish.jersey.version}</version>
+      </dependency>
 
       <dependency>
         <groupId>org.glassfish.jersey.test-framework.providers</groupId>
@@ -295,10 +302,10 @@
       </dependency>
       
       <dependency>
-	      <groupId>org.hibernate</groupId>
-	      <artifactId>hibernate-validator</artifactId>
-	      <version>${org.hibernate.hibernate.version}</version>
-	    </dependency>
+        <groupId>org.hibernate</groupId>
+        <artifactId>hibernate-validator</artifactId>
+        <version>${org.hibernate.hibernate.version}</version>
+      </dependency>
       
       <dependency>
         <groupId>commons-dbcp</groupId>
@@ -354,6 +361,13 @@
         <version>${org.bouncycastle.bcprov-jdk15on.version}</version>
       </dependency>
       
+      <!-- Used to read JBIG2 images. See https://github.com/sismics/docs/issues/38 -->
+      <dependency>
+        <groupId>com.levigo.jbig2</groupId>
+        <artifactId>levigo-jbig2-imageio</artifactId>
+        <version>${com.levigo.jbig2.levigo-jbig2-imageio.version}</version>
+      </dependency>
+      
       <!-- OCR dependencies -->
       <dependency>
         <groupId>jna</groupId>
diff --git a/docs-web/src/dev/resources/config.properties b/docs-web/src/dev/resources/config.properties
index f2362d2f..87577f48 100644
--- a/docs-web/src/dev/resources/config.properties
+++ b/docs-web/src/dev/resources/config.properties
@@ -1,3 +1,3 @@
 api.current_version=${project.version}
 api.min_version=1.0
-db.version=1
\ No newline at end of file
+db.version=2
\ No newline at end of file
diff --git a/docs-web/src/main/java/com/sismics/docs/rest/resource/AuditLogResource.java b/docs-web/src/main/java/com/sismics/docs/rest/resource/AuditLogResource.java
index 8c128e06..a1ad4e72 100644
--- a/docs-web/src/main/java/com/sismics/docs/rest/resource/AuditLogResource.java
+++ b/docs-web/src/main/java/com/sismics/docs/rest/resource/AuditLogResource.java
@@ -19,6 +19,7 @@ import com.sismics.docs.core.util.jpa.PaginatedLists;
 import com.sismics.docs.core.util.jpa.SortCriteria;
 import com.sismics.rest.exception.ForbiddenClientException;
 import com.sismics.rest.exception.ServerException;
+import com.sismics.rest.util.JsonUtil;
 
 /**
  * Audit log REST resources.
@@ -70,7 +71,7 @@ public class AuditLogResource extends BaseResource {
                     .add("target", auditLogDto.getEntityId())
                     .add("class", auditLogDto.getEntityClass())
                     .add("type", auditLogDto.getType().name())
-                    .add("message", auditLogDto.getMessage())
+                    .add("message", JsonUtil.nullable(auditLogDto.getMessage()))
                     .add("create_date", auditLogDto.getCreateTimestamp()));
         }
 
diff --git a/docs-web/src/main/java/com/sismics/docs/rest/resource/TagResource.java b/docs-web/src/main/java/com/sismics/docs/rest/resource/TagResource.java
index 05b8cc4b..11883aab 100644
--- a/docs-web/src/main/java/com/sismics/docs/rest/resource/TagResource.java
+++ b/docs-web/src/main/java/com/sismics/docs/rest/resource/TagResource.java
@@ -22,6 +22,7 @@ import com.sismics.docs.core.dao.jpa.dto.TagStatDto;
 import com.sismics.docs.core.model.jpa.Tag;
 import com.sismics.rest.exception.ClientException;
 import com.sismics.rest.exception.ForbiddenClientException;
+import com.sismics.rest.util.JsonUtil;
 import com.sismics.rest.util.ValidationUtil;
 
 /**
@@ -50,7 +51,8 @@ public class TagResource extends BaseResource {
             items.add(Json.createObjectBuilder()
                     .add("id", tag.getId())
                     .add("name", tag.getName())
-                    .add("color", tag.getColor()));
+                    .add("color", tag.getColor())
+                    .add("parent", JsonUtil.nullable(tag.getParentId())));
         }
         
         JsonObjectBuilder response = Json.createObjectBuilder()
@@ -96,7 +98,8 @@ public class TagResource extends BaseResource {
     @PUT
     public Response add(
             @FormParam("name") String name,
-            @FormParam("color") String color) {
+            @FormParam("color") String color,
+            @FormParam("parent") String parentId) {
         if (!authenticate()) {
             throw new ForbiddenClientException();
         }
@@ -117,11 +120,22 @@ public class TagResource extends BaseResource {
             throw new ClientException("AlreadyExistingTag", MessageFormat.format("Tag already exists: {0}", name));
         }
         
+        // Check the parent
+        if (StringUtils.isEmpty(parentId)) {
+            parentId = null;
+        } else {
+            Tag parentTag = tagDao.getByTagId(principal.getId(), parentId);
+            if (parentTag == null) {
+                throw new ClientException("ParentNotFound", MessageFormat.format("Parent not found: {0}", parentId));
+            }
+        }
+        
         // Create the tag
         tag = new Tag();
         tag.setName(name);
         tag.setColor(color);
         tag.setUserId(principal.getId());
+        tag.setParentId(parentId);
         String id = tagDao.create(tag);
         
         JsonObjectBuilder response = Json.createObjectBuilder()
@@ -140,7 +154,8 @@ public class TagResource extends BaseResource {
     public Response update(
             @PathParam("id") String id,
             @FormParam("name") String name,
-            @FormParam("color") String color) {
+            @FormParam("color") String color,
+            @FormParam("parent") String parentId) {
         if (!authenticate()) {
             throw new ForbiddenClientException();
         }
@@ -161,6 +176,16 @@ public class TagResource extends BaseResource {
             throw new ClientException("TagNotFound", MessageFormat.format("Tag not found: {0}", id));
         }
         
+        // Check the parent
+        if (StringUtils.isEmpty(parentId)) {
+            parentId = null;
+        } else {
+            Tag parentTag = tagDao.getByTagId(principal.getId(), parentId);
+            if (parentTag == null) {
+                throw new ClientException("ParentNotFound", MessageFormat.format("Parent not found: {0}", parentId));
+            }
+        }
+        
         // Check for name duplicate
         Tag tagDuplicate = tagDao.getByName(principal.getId(), name);
         if (tagDuplicate != null && !tagDuplicate.getId().equals(id)) {
@@ -174,6 +199,8 @@ public class TagResource extends BaseResource {
         if (!StringUtils.isEmpty(color)) {
             tag.setColor(color);
         }
+        // Parent tag is always updated to have the possibility to delete it
+        tag.setParentId(parentId);
         
         tagDao.update(tag);
         
diff --git a/docs-web/src/main/java/com/sismics/docs/rest/resource/UserResource.java b/docs-web/src/main/java/com/sismics/docs/rest/resource/UserResource.java
index 501a4e9b..b1fe41eb 100644
--- a/docs-web/src/main/java/com/sismics/docs/rest/resource/UserResource.java
+++ b/docs-web/src/main/java/com/sismics/docs/rest/resource/UserResource.java
@@ -40,6 +40,7 @@ import com.sismics.docs.rest.constant.BaseFunction;
 import com.sismics.rest.exception.ClientException;
 import com.sismics.rest.exception.ForbiddenClientException;
 import com.sismics.rest.exception.ServerException;
+import com.sismics.rest.util.JsonUtil;
 import com.sismics.rest.util.ValidationUtil;
 import com.sismics.security.UserPrincipal;
 import com.sismics.util.filter.TokenBasedSecurityFilter;
@@ -513,8 +514,8 @@ public class UserResource extends BaseResource {
         for (AuthenticationToken authenticationToken : authenticationTokenDao.getByUserId(principal.getId())) {
             JsonObjectBuilder session = Json.createObjectBuilder()
                     .add("create_date", authenticationToken.getCreationDate().getTime())
-                    .add("ip", authenticationToken.getIp())
-                    .add("user_agent", authenticationToken.getUserAgent());
+                    .add("ip", JsonUtil.nullable(authenticationToken.getIp()))
+                    .add("user_agent", JsonUtil.nullable(authenticationToken.getUserAgent()));
             if (authenticationToken.getLastConnectionDate() != null) {
                 session.add("last_connection_date", authenticationToken.getLastConnectionDate().getTime());
             }
diff --git a/docs-web/src/main/webapp/src/app/docs/app.js b/docs-web/src/main/webapp/src/app/docs/app.js
index 4a88388a..5a1860c3 100644
--- a/docs-web/src/main/webapp/src/app/docs/app.js
+++ b/docs-web/src/main/webapp/src/app/docs/app.js
@@ -125,6 +125,9 @@ angular.module('docs',
         }
       }
     })
+      .state('document.default.search', {
+        url: '/search/:search'
+      })
       .state('document.default.file', {
         url: '/file/:fileId',
         views: {
@@ -153,6 +156,7 @@ angular.module('docs',
     })
     .state('document.view', {
       url: '/view/:id',
+      redirectTo: 'document.view.content',
       views: {
         'document': {
           templateUrl: 'partial/docs/document.view.html',
@@ -160,6 +164,33 @@ angular.module('docs',
         }
       }
     })
+      .state('document.view.content', {
+        url: '/content',
+        views: {
+          'tab': {
+            templateUrl: 'partial/docs/document.view.content.html',
+            controller: 'DocumentViewContent'
+          }
+        }
+      })
+      .state('document.view.permissions', {
+        url: '/permissions',
+        views: {
+          'tab': {
+            templateUrl: 'partial/docs/document.view.permissions.html',
+            controller: 'DocumentViewPermissions'
+          }
+        }
+      })
+      .state('document.view.activity', {
+        url: '/activity',
+        views: {
+          'tab': {
+            templateUrl: 'partial/docs/document.view.activity.html',
+            controller: 'DocumentViewActivity'
+          }
+        }
+      })
       .state('document.view.file', {
         url: '/file/:fileId',
         views: {
@@ -228,4 +259,18 @@ angular.module('docs',
   $rootScope.$state = $state;
   $rootScope.$stateParams = $stateParams;
   $rootScope.pageTitle = 'Sismics Docs';
+})
+/**
+ * Redirection support for ui-router.
+ * Thanks to https://github.com/acollard
+ * See https://github.com/angular-ui/ui-router/issues/1584#issuecomment-76993045
+ */
+.run(function($rootScope, $state){
+  $rootScope.$on('$stateChangeStart', function(event, toState, toParams) {
+    var redirect = toState.redirectTo;
+    if (redirect) {
+      event.preventDefault();
+      $state.go(redirect, toParams);
+    }
+  });
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/Document.js b/docs-web/src/main/webapp/src/app/docs/controller/Document.js
index 6af0d944..4497d41a 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/Document.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/Document.js
@@ -12,7 +12,8 @@ angular.module('docs').controller('Document', function($scope, $timeout, $state,
   $scope.offset = 0;
   $scope.currentPage = 1;
   $scope.limit = _.isUndefined(localStorage.documentsPageSize) ? 10 : localStorage.documentsPageSize;
-  $scope.search = '';
+  $scope.search = $state.params.search ? $state.params.search : '';
+  $scope.setSearch = function(search) { $scope.search = search };
 
   // A timeout promise is used to slow down search requests to the server
   // We keep track of it for cancellation purpose
@@ -65,6 +66,17 @@ angular.module('docs').controller('Document', function($scope, $timeout, $state,
       $timeout.cancel(timeoutPromise);
     }
 
+    if ($state.current.name == 'document.default'
+        || $state.current.name == 'document.default.search') {
+      $state.go($scope.search == '' ?
+          'document.default' : 'document.default.search', {
+        search: $scope.search
+      }, {
+        location: 'replace',
+        notify: false
+      });
+    }
+
     // Call API later
     timeoutPromise = $timeout(function () {
       $scope.loadDocuments();
@@ -99,6 +111,22 @@ angular.module('docs').controller('Document', function($scope, $timeout, $state,
    * Display a document.
    */
   $scope.viewDocument = function(id) {
-    $state.transitionTo('document.view', { id: id });
+    $state.go('document.view', { id: id });
+  };
+
+  // Load tags
+  var tags = [];
+  Restangular.one('tag/list').getList().then(function(data) {
+    tags = data.tags;
+  });
+
+  /**
+   * Find children tags.
+   * @param parent
+   */
+  $scope.getChildrenTags = function(parent) {
+    return _.filter(tags, function(tag) {
+      return tag.parent == parent;
+    });
   };
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/DocumentDefault.js b/docs-web/src/main/webapp/src/app/docs/controller/DocumentDefault.js
index e5433e09..361ef241 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/DocumentDefault.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/DocumentDefault.js
@@ -81,7 +81,7 @@ angular.module('docs').controller('DocumentDefault', function($scope, $state, Re
    * Navigate to the selected file.
    */
   $scope.openFile = function (file) {
-    $state.transitionTo('document.default.file', { fileId: file.id })
+    $state.go('document.default.file', { fileId: file.id })
   };
 
   /**
@@ -107,6 +107,6 @@ angular.module('docs').controller('DocumentDefault', function($scope, $state, Re
    * Add a document with checked files.
    */
   $scope.addDocument = function() {
-    $state.transitionTo('document.add', { files: _.pluck($scope.checkedFiles(), 'id') });
+    $state.go('document.add', { files: _.pluck($scope.checkedFiles(), 'id') });
   };
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/DocumentEdit.js b/docs-web/src/main/webapp/src/app/docs/controller/DocumentEdit.js
index c0d7d4b3..c9141ec7 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/DocumentEdit.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/DocumentEdit.js
@@ -95,7 +95,7 @@ angular.module('docs').controller('DocumentEdit', function($rootScope, $scope, $
           if ($scope.isEdit()) {
             // Go back to the edited document
             $scope.pageDocuments();
-            $state.transitionTo('document.view', { id: $stateParams.id });
+            $state.go('document.view', { id: $stateParams.id });
           } else {
             // Reset the scope and stay here
             var fileUploadCount = _.size($scope.newFiles) + resolve.length;
@@ -188,9 +188,9 @@ angular.module('docs').controller('DocumentEdit', function($rootScope, $scope, $
    */
   $scope.cancel = function() {
     if ($scope.isEdit()) {
-      $state.transitionTo('document.view', { id: $stateParams.id });
+      $state.go('document.view', { id: $stateParams.id });
     } else {
-      $state.transitionTo('document.default');
+      $state.go('document.default');
     }
   };
 
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/DocumentView.js b/docs-web/src/main/webapp/src/app/docs/controller/DocumentView.js
index 8962c884..bf71478d 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/DocumentView.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/DocumentView.js
@@ -3,7 +3,7 @@
 /**
  * Document view controller.
  */
-angular.module('docs').controller('DocumentView', function ($scope, $state, $stateParams, $location, $dialog, $modal, Restangular, $upload, $q) {
+angular.module('docs').controller('DocumentView', function ($scope, $state, $stateParams, $location, $dialog, $modal, Restangular, $timeout) {
   // Load document data from server
   Restangular.one('document', $stateParams.id).get().then(function(data) {
     $scope.document = data;
@@ -11,60 +11,6 @@ angular.module('docs').controller('DocumentView', function ($scope, $state, $sta
     $scope.error = response;
   });
 
-  // Load audit log data from server
-  Restangular.one('auditlog').get({
-    document: $stateParams.id
-  }).then(function(data) {
-    $scope.logs = data.logs;
-  });
-
-  // Watch for ACLs change and group them for easy displaying
-  $scope.$watch('document.acls', function(acls) {
-    $scope.acls = _.groupBy(acls, function(acl) {
-      return acl.id;
-    });
-  });
-
-  // Initialize add ACL
-  $scope.acl = { perm: 'READ' };
-
-  /**
-   * Configuration for file sorting.
-   */
-  $scope.fileSortableOptions = {
-    forceHelperSize: true,
-    forcePlaceholderSize: true,
-    tolerance: 'pointer',
-    handle: '.handle',
-    stop: function () {
-      // Send new positions to server
-      $scope.$apply(function () {
-        Restangular.one('file').post('reorder', {
-          id: $stateParams.id,
-          order: _.pluck($scope.files, 'id')
-        });
-      });
-    }
-  };
-
-  /**
-   * Load files from server.
-   */
-  $scope.loadFiles = function () {
-    Restangular.one('file').getList('list', { id: $stateParams.id }).then(function (data) {
-      $scope.files = data.files;
-      // TODO Keep currently uploading files
-    });
-  };
-  $scope.loadFiles();
-
-  /**
-   * Navigate to the selected file.
-   */
-  $scope.openFile = function (file) {
-    $state.transitionTo('document.view.file', { id: $stateParams.id, fileId: file.id })
-  };
-
   /**
    * Delete a document.
    */
@@ -80,27 +26,7 @@ angular.module('docs').controller('DocumentView', function ($scope, $state, $sta
       if (result == 'ok') {
         Restangular.one('document', document.id).remove().then(function () {
           $scope.loadDocuments();
-          $state.transitionTo('document.default');
-        });
-      }
-    });
-  };
-
-  /**
-   * Delete a file.
-   */
-  $scope.deleteFile = function (file) {
-    var title = 'Delete file';
-    var msg = 'Do you really want to delete this file?';
-    var btns = [
-      {result: 'cancel', label: 'Cancel'},
-      {result: 'ok', label: 'OK', cssClass: 'btn-primary'}
-    ];
-
-    $dialog.messageBox(title, msg, btns, function (result) {
-      if (result == 'ok') {
-        Restangular.one('file', file.id).remove().then(function () {
-          $scope.loadFiles();
+          $state.go('document.default');
         });
       }
     });
@@ -157,125 +83,4 @@ angular.module('docs').controller('DocumentView', function ($scope, $state, $sta
       }
     });
   };
-
-  /**
-   * File has been drag & dropped.
-   */
-  $scope.fileDropped = function(files) {
-    if (!$scope.document.writable) {
-      return;
-    }
-
-    if (files && files.length) {
-      // Adding files to the UI
-      var newfiles = [];
-      _.each(files, function(file) {
-        var newfile = {
-          progress: 0,
-          name: file.name,
-          create_date: new Date().getTime(),
-          mimetype: file.type,
-          status: 'Pending...'
-        };
-        $scope.files.push(newfile);
-        newfiles.push(newfile);
-      });
-
-      // Uploading files sequentially
-      var key = 0;
-      var then = function() {
-        if (files[key]) {
-          $scope.uploadFile(files[key], newfiles[key++]).then(then);
-        }
-      };
-      then();
-    }
-  };
-
-  /**
-   * Upload a file.
-   */
-  $scope.uploadFile = function(file, newfile) {
-    // Upload the file
-    newfile.status = 'Uploading...';
-    return $upload.upload({
-      method: 'PUT',
-      url: '../api/file',
-      file: file,
-      fields: {
-        id: $stateParams.id
-      }
-    })
-        .progress(function (e) {
-          newfile.progress = parseInt(100.0 * e.loaded / e.total);
-        })
-        .success(function (data) {
-          newfile.id = data.id;
-        });
-  };
-
-  /**
-   * Delete an ACL.
-   */
-  $scope.deleteAcl = function(acl) {
-    Restangular.one('acl/' + $stateParams.id + '/' + acl.perm + '/' + acl.id, null).remove().then(function () {
-      $scope.document.acls = _.reject($scope.document.acls, function(s) {
-        return angular.equals(acl, s);
-      });
-    });
-  };
-
-  /**
-   * Add an ACL.
-   */
-  $scope.addAcl = function() {
-    // Compute ACLs to add
-    $scope.acl.source = $stateParams.id;
-    var acls = [];
-    if ($scope.acl.perm == 'READWRITE') {
-      acls = [{
-        source: $stateParams.id,
-        username: $scope.acl.username,
-        perm: 'READ'
-      }, {
-        source: $stateParams.id,
-        username: $scope.acl.username,
-        perm: 'WRITE'
-      }];
-    } else {
-      acls = [{
-        source: $stateParams.id,
-        username: $scope.acl.username,
-        perm: $scope.acl.perm
-      }];
-    }
-
-    // Add ACLs
-    _.each(acls, function(acl) {
-      Restangular.one('acl').put(acl).then(function(acl) {
-        if (_.isUndefined(acl.id)) {
-          return;
-        }
-        $scope.document.acls.push(acl);
-        $scope.document.acls = angular.copy($scope.document.acls);
-      });
-    });
-
-    // Reset form
-    $scope.acl = { perm: 'READ' };
-  };
-
-  /**
-   * Auto-complete on ACL target.
-   */
-  $scope.getTargetAclTypeahead = function($viewValue) {
-    var deferred = $q.defer();
-    Restangular.one('acl/target/search')
-        .get({
-          search: $viewValue
-        }).then(function(data) {
-          deferred.resolve(_.pluck(data.users, 'username'), true);
-        });
-    return deferred.promise;
-  };
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewActivity.js b/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewActivity.js
new file mode 100644
index 00000000..09e702fb
--- /dev/null
+++ b/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewActivity.js
@@ -0,0 +1,13 @@
+'use strict';
+
+/**
+ * Document view activity controller.
+ */
+angular.module('docs').controller('DocumentViewActivity', function ($scope, $stateParams, Restangular) {
+  // Load audit log data from server
+  Restangular.one('auditlog').get({
+    document: $stateParams.id
+  }).then(function(data) {
+    $scope.logs = data.logs;
+  });
+});
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewContent.js b/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewContent.js
new file mode 100644
index 00000000..bab5b48d
--- /dev/null
+++ b/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewContent.js
@@ -0,0 +1,119 @@
+'use strict';
+
+/**
+ * Document view content controller.
+ */
+angular.module('docs').controller('DocumentViewContent', function ($scope, $stateParams, Restangular, $dialog, $state, $upload) {
+  /**
+   * Configuration for file sorting.
+   */
+  $scope.fileSortableOptions = {
+    forceHelperSize: true,
+    forcePlaceholderSize: true,
+    tolerance: 'pointer',
+    handle: '.handle',
+    stop: function () {
+      // Send new positions to server
+      $scope.$apply(function () {
+        Restangular.one('file').post('reorder', {
+          id: $stateParams.id,
+          order: _.pluck($scope.files, 'id')
+        });
+      });
+    }
+  };
+
+  /**
+   * Load files from server.
+   */
+  $scope.loadFiles = function () {
+    Restangular.one('file').getList('list', { id: $stateParams.id }).then(function (data) {
+      $scope.files = data.files;
+      // TODO Keep currently uploading files
+    });
+  };
+  $scope.loadFiles();
+
+  /**
+   * Navigate to the selected file.
+   */
+  $scope.openFile = function (file) {
+    $state.go('document.view.file', { id: $stateParams.id, fileId: file.id })
+  };
+
+  /**
+   * Delete a file.
+   */
+  $scope.deleteFile = function (file) {
+    var title = 'Delete file';
+    var msg = 'Do you really want to delete this file?';
+    var btns = [
+      {result: 'cancel', label: 'Cancel'},
+      {result: 'ok', label: 'OK', cssClass: 'btn-primary'}
+    ];
+
+    $dialog.messageBox(title, msg, btns, function (result) {
+      if (result == 'ok') {
+        Restangular.one('file', file.id).remove().then(function () {
+          $scope.loadFiles();
+        });
+      }
+    });
+  };
+
+  /**
+   * File has been drag & dropped.
+   */
+  $scope.fileDropped = function(files) {
+    if (!$scope.document.writable) {
+      return;
+    }
+
+    if (files && files.length) {
+      // Adding files to the UI
+      var newfiles = [];
+      _.each(files, function(file) {
+        var newfile = {
+          progress: 0,
+          name: file.name,
+          create_date: new Date().getTime(),
+          mimetype: file.type,
+          status: 'Pending...'
+        };
+        $scope.files.push(newfile);
+        newfiles.push(newfile);
+      });
+
+      // Uploading files sequentially
+      var key = 0;
+      var then = function() {
+        if (files[key]) {
+          $scope.uploadFile(files[key], newfiles[key++]).then(then);
+        }
+      };
+      then();
+    }
+  };
+
+  /**
+   * Upload a file.
+   */
+  $scope.uploadFile = function(file, newfile) {
+    // Upload the file
+    newfile.status = 'Uploading...';
+    return $upload.upload({
+      method: 'PUT',
+      url: '../api/file',
+      file: file,
+      fields: {
+        id: $stateParams.id
+      }
+    })
+        .progress(function (e) {
+          newfile.progress = parseInt(100.0 * e.loaded / e.total);
+        })
+        .success(function (data) {
+          newfile.id = data.id;
+        });
+  };
+});
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewPermissions.js b/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewPermissions.js
new file mode 100644
index 00000000..2c6ecb5f
--- /dev/null
+++ b/docs-web/src/main/webapp/src/app/docs/controller/DocumentViewPermissions.js
@@ -0,0 +1,81 @@
+'use strict';
+
+/**
+ * Document view permissions controller.
+ */
+angular.module('docs').controller('DocumentViewPermissions', function ($scope, $stateParams, Restangular, $q) {
+  // Watch for ACLs change and group them for easy displaying
+  $scope.$watch('document.acls', function(acls) {
+    $scope.acls = _.groupBy(acls, function(acl) {
+      return acl.id;
+    });
+  });
+
+  // Initialize add ACL
+  $scope.acl = { perm: 'READ' };
+
+  /**
+   * Delete an ACL.
+   */
+  $scope.deleteAcl = function(acl) {
+    Restangular.one('acl/' + $stateParams.id + '/' + acl.perm + '/' + acl.id, null).remove().then(function () {
+      $scope.document.acls = _.reject($scope.document.acls, function(s) {
+        return angular.equals(acl, s);
+      });
+    });
+  };
+
+  /**
+   * Add an ACL.
+   */
+  $scope.addAcl = function() {
+    // Compute ACLs to add
+    $scope.acl.source = $stateParams.id;
+    var acls = [];
+    if ($scope.acl.perm == 'READWRITE') {
+      acls = [{
+        source: $stateParams.id,
+        username: $scope.acl.username,
+        perm: 'READ'
+      }, {
+        source: $stateParams.id,
+        username: $scope.acl.username,
+        perm: 'WRITE'
+      }];
+    } else {
+      acls = [{
+        source: $stateParams.id,
+        username: $scope.acl.username,
+        perm: $scope.acl.perm
+      }];
+    }
+
+    // Add ACLs
+    _.each(acls, function(acl) {
+      Restangular.one('acl').put(acl).then(function(acl) {
+        if (_.isUndefined(acl.id)) {
+          return;
+        }
+        $scope.document.acls.push(acl);
+        $scope.document.acls = angular.copy($scope.document.acls);
+      });
+    });
+
+    // Reset form
+    $scope.acl = { perm: 'READ' };
+  };
+
+  /**
+   * Auto-complete on ACL target.
+   */
+  $scope.getTargetAclTypeahead = function($viewValue) {
+    var deferred = $q.defer();
+    Restangular.one('acl/target/search')
+        .get({
+          search: $viewValue
+        }).then(function(data) {
+          deferred.resolve(_.pluck(data.users, 'username'), true);
+        });
+    return deferred.promise;
+  };
+});
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/Login.js b/docs-web/src/main/webapp/src/app/docs/controller/Login.js
index 14340858..9c695aa3 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/Login.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/Login.js
@@ -9,7 +9,7 @@ angular.module('docs').controller('Login', function($scope, $rootScope, $state,
       User.userInfo(true).then(function(data) {
         $rootScope.userInfo = data;
       });
-      $state.transitionTo('document.default');
+      $state.go('document.default');
     }, function() {
       var title = 'Login failed';
       var msg = 'Username or password invalid';
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/Main.js b/docs-web/src/main/webapp/src/app/docs/controller/Main.js
index bb56d24e..5dc8ad0d 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/Main.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/Main.js
@@ -6,9 +6,13 @@
 angular.module('docs').controller('Main', function($scope, $rootScope, $state, User) {
   User.userInfo().then(function(data) {
     if (data.anonymous) {
-      $state.transitionTo('login');
+      $state.go('login', {}, {
+        location: 'replace'
+      });
     } else {
-      $state.transitionTo('document.default');
+      $state.go('document.default', {}, {
+        location: 'replace'
+      });
     }
   });
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/Navigation.js b/docs-web/src/main/webapp/src/app/docs/controller/Navigation.js
index 64417aa9..d21bbb09 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/Navigation.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/Navigation.js
@@ -41,7 +41,7 @@ angular.module('docs').controller('Navigation', function($scope, $http, $state,
    */
   $scope.openLogs = function() {
     $scope.errorNumber = 0;
-    $state.transitionTo('settings.log');
+    $state.go('settings.log');
   };
 
   /**
@@ -52,7 +52,7 @@ angular.module('docs').controller('Navigation', function($scope, $http, $state,
       User.userInfo(true).then(function(data) {
         $rootScope.userInfo = data;
       });
-      $state.transitionTo('main');
+      $state.go('main');
     });
     $event.preventDefault();
   };
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/SettingsUser.js b/docs-web/src/main/webapp/src/app/docs/controller/SettingsUser.js
index f65160aa..8a499264 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/SettingsUser.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/SettingsUser.js
@@ -19,6 +19,6 @@ angular.module('docs').controller('SettingsUser', function($scope, $state, Resta
    * Edit a user.
    */
   $scope.editUser = function(user) {
-    $state.transitionTo('settings.user.edit', { username: user.username });
+    $state.go('settings.user.edit', { username: user.username });
   };
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/docs/controller/SettingsUserEdit.js b/docs-web/src/main/webapp/src/app/docs/controller/SettingsUserEdit.js
index ecd4d027..91537989 100644
--- a/docs-web/src/main/webapp/src/app/docs/controller/SettingsUserEdit.js
+++ b/docs-web/src/main/webapp/src/app/docs/controller/SettingsUserEdit.js
@@ -38,7 +38,7 @@ angular.module('docs').controller('SettingsUserEdit', function($scope, $dialog,
     
     promise.then(function() {
       $scope.loadUsers();
-      $state.transitionTo('settings.user');
+      $state.go('settings.user');
     });
   };
 
@@ -54,9 +54,9 @@ angular.module('docs').controller('SettingsUserEdit', function($scope, $dialog,
       if (result == 'ok') {
         Restangular.one('user', $stateParams.username).remove().then(function() {
           $scope.loadUsers();
-          $state.transitionTo('settings.user');
+          $state.go('settings.user');
         }, function () {
-          $state.transitionTo('settings.user');
+          $state.go('settings.user');
         });
       }
     });
diff --git a/docs-web/src/main/webapp/src/app/share/controller/FileModalView.js b/docs-web/src/main/webapp/src/app/share/controller/FileModalView.js
index 8426022d..f705378c 100644
--- a/docs-web/src/main/webapp/src/app/share/controller/FileModalView.js
+++ b/docs-web/src/main/webapp/src/app/share/controller/FileModalView.js
@@ -24,7 +24,7 @@ angular.module('share').controller('FileModalView', function($rootScope, $modalI
       if (value.id == $stateParams.fileId) {
         var next = $scope.files[key + 1];
         if (next) {
-          $state.transitionTo('share.file', { documentId: $stateParams.documentId, shareId: $stateParams.shareId, fileId: next.id });
+          $state.go('share.file', { documentId: $stateParams.documentId, shareId: $stateParams.shareId, fileId: next.id });
         }
       }
     });
@@ -38,7 +38,7 @@ angular.module('share').controller('FileModalView', function($rootScope, $modalI
       if (value.id == $stateParams.fileId) {
         var previous = $scope.files[key - 1];
         if (previous) {
-          $state.transitionTo('share.file', { documentId: $stateParams.documentId, shareId: $stateParams.shareId,  fileId: previous.id });
+          $state.go('share.file', { documentId: $stateParams.documentId, shareId: $stateParams.shareId,  fileId: previous.id });
         }
       }
     });
diff --git a/docs-web/src/main/webapp/src/app/share/controller/FileView.js b/docs-web/src/main/webapp/src/app/share/controller/FileView.js
index 3ea83514..07e45b23 100644
--- a/docs-web/src/main/webapp/src/app/share/controller/FileView.js
+++ b/docs-web/src/main/webapp/src/app/share/controller/FileView.js
@@ -16,6 +16,6 @@ angular.module('share').controller('FileView', function($modal, $state, $statePa
     modal.closed = true;
   },function(result) {
     modal.closed = true;
-    $state.transitionTo('share', { documentId: $stateParams.documentId, shareId: $stateParams.shareId });
+    $state.go('share', { documentId: $stateParams.documentId, shareId: $stateParams.shareId });
   });
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/app/share/controller/Share.js b/docs-web/src/main/webapp/src/app/share/controller/Share.js
index f3ddda15..c1e15ae6 100644
--- a/docs-web/src/main/webapp/src/app/share/controller/Share.js
+++ b/docs-web/src/main/webapp/src/app/share/controller/Share.js
@@ -10,7 +10,7 @@ angular.module('share').controller('Share', function($scope, $state, $stateParam
         $scope.document = data;
       }, function (response) {
         if (response.status == 403) {
-          $state.transitionTo('403');
+          $state.go('403');
         }
       });
 
@@ -24,6 +24,6 @@ angular.module('share').controller('Share', function($scope, $state, $stateParam
    * Navigate to the selected file.
    */
   $scope.openFile = function (file) {
-    $state.transitionTo('share.file', { documentId: $stateParams.documentId, shareId: $stateParams.shareId, fileId: file.id })
+    $state.go('share.file', { documentId: $stateParams.documentId, shareId: $stateParams.shareId, fileId: file.id })
   };
 });
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/index.html b/docs-web/src/main/webapp/src/index.html
index 6247f46b..9fb47b64 100644
--- a/docs-web/src/main/webapp/src/index.html
+++ b/docs-web/src/main/webapp/src/index.html
@@ -43,6 +43,9 @@
     <script src="app/docs/controller/DocumentDefault.js" type="text/javascript"></script>
     <script src="app/docs/controller/DocumentEdit.js" type="text/javascript"></script>
     <script src="app/docs/controller/DocumentView.js" type="text/javascript"></script>
+    <script src="app/docs/controller/DocumentViewContent.js" type="text/javascript"></script>
+    <script src="app/docs/controller/DocumentViewPermissions.js" type="text/javascript"></script>
+    <script src="app/docs/controller/DocumentViewActivity.js" type="text/javascript"></script>
     <script src="app/docs/controller/DocumentModalShare.js" type="text/javascript"></script>
     <script src="app/docs/controller/FileView.js" type="text/javascript"></script>
     <script src="app/docs/controller/FileModalView.js" type="text/javascript"></script>
diff --git a/docs-web/src/main/webapp/src/partial/docs/document.html b/docs-web/src/main/webapp/src/partial/docs/document.html
index e4b91b11..207e4374 100644
--- a/docs-web/src/main/webapp/src/partial/docs/document.html
+++ b/docs-web/src/main/webapp/src/partial/docs/document.html
@@ -5,49 +5,61 @@
         <a href="#/document/add" class="btn btn-primary"><span class="glyphicon glyphicon-plus"></span> Add a document</a>
       </p>
 
-      <div class="input-group">
-        <span class="input-group-addon">
-          <span class="glyphicon glyphicon glyphicon-info-sign"
-            tooltip-placement="bottom"
-            tooltip-html-unsafe="before:2012-05<br/>
-            after:2012-05<br/>
-            at:2012-05<br/>
-            tag:car<br/>
-            full:led<br/>
-            shared:yes<br/>
-            lang:fra"></span>
-        </span>
-        <input type="search" class="form-control" placeholder="Search" ng-model="search" />
-        <span class="input-group-addon">
-          <span class="glyphicon glyphicon-search" ng-show="search.length == 0"></span>
-          <span class="glyphicon glyphicon-remove" ng-show="search.length > 0" ng-click="search = ''"></span>
-        </span>
+      <div class="row">
+        <div class="dropdown col-md-2 tag-tree-dropdown" dropdown>
+          <button class="btn btn-block btn-default" dropdown-toggle ng-disabled="disabled">
+            Tags <span class="caret"></span>
+          </button>
+          <ul class="dropdown-menu tag-tree">
+            <li ng-if="getChildrenTags().length == 0">No tags</li>
+            <li ng-repeat="tag in getChildrenTags()" ng-include="'tag-tree-item'"></li>
+          </ul>
+        </div>
+
+        <div class="col-md-10 input-group">
+          <span class="input-group-addon">
+            <span class="glyphicon glyphicon glyphicon-info-sign"
+                  tooltip-placement="bottom"
+                  tooltip-html-unsafe="before:2012-05<br/>
+              after:2012-05<br/>
+              at:2012-05<br/>
+              tag:car<br/>
+              full:led<br/>
+              shared:yes<br/>
+              lang:fra"></span>
+          </span>
+          <input type="search" class="form-control" placeholder="Search" ng-model="search" />
+          <span class="input-group-addon">
+            <span class="glyphicon glyphicon-search" ng-show="search.length == 0"></span>
+            <span class="glyphicon glyphicon-remove" ng-show="search.length > 0" ng-click="search = ''"></span>
+          </span>
+        </div>
       </div>
 
       <table class="row table table-striped table-hover table-documents">
         <thead>
-          <tr>
-            <th class="col-xs-6" ng-click="sortDocuments(1)"><span class="glyphicon glyphicon-chevron-{{ sortColumn == 1 ? (asc ? 'down' : 'up') : '' }}"></span> Title</th>
-            <th class="col-xs-3" ng-click="sortDocuments(3)"><span class="glyphicon glyphicon-chevron-{{ sortColumn == 3 ? (asc ? 'down' : 'up') : '' }}"></span> Creation date</th>
-            <th class="col-xs-3 hidden-xs">Tags</th>
-          </tr>
+        <tr>
+          <th class="col-xs-6" ng-click="sortDocuments(1)"><span class="glyphicon glyphicon-chevron-{{ sortColumn == 1 ? (asc ? 'down' : 'up') : '' }}"></span> Title</th>
+          <th class="col-xs-3" ng-click="sortDocuments(3)"><span class="glyphicon glyphicon-chevron-{{ sortColumn == 3 ? (asc ? 'down' : 'up') : '' }}"></span> Creation date</th>
+          <th class="col-xs-3 hidden-xs">Tags</th>
+        </tr>
         </thead>
         <tbody>
-          <tr ng-click="viewDocument(document.id)" ng-repeat="document in documents">
-            <td>
-              {{ document.title }} ({{ document.file_count }})
-              <span class="glyphicon glyphicon-share" ng-if="document.shared" tooltip="Shared"></span>
-              <a href="#/document/view/{{ document.id }}" ng-click="$event.stopPropagation()"><span class="glyphicon glyphicon-link"></span></a>
-            </td>
-            <td>{{ document.create_date | date: 'yyyy-MM-dd' }}</td>
-            <td class="hidden-xs cell-tags">
-              <div class="tags">
-                <span class="label label-info" ng-repeat="tag in document.tags" ng-style="{ 'background': tag.color }">
-                  <span class="shorten">{{ tag.name | shorten }}</span><span class="full">{{ tag.name }}</span>
-                </span>
-              </div>
-            </td>
-          </tr>
+        <tr ng-click="viewDocument(document.id)" ng-repeat="document in documents">
+          <td>
+            {{ document.title }} ({{ document.file_count }})
+            <span class="glyphicon glyphicon-share" ng-if="document.shared" tooltip="Shared"></span>
+            <a href="#/document/view/{{ document.id }}" target="_blank" ng-click="$event.stopPropagation()"><span class="glyphicon glyphicon-link"></span></a>
+          </td>
+          <td>{{ document.create_date | date: 'yyyy-MM-dd' }}</td>
+          <td class="hidden-xs cell-tags">
+            <div class="tags">
+            <span class="label label-info" ng-repeat="tag in document.tags" ng-style="{ 'background': tag.color }">
+              <span class="shorten">{{ tag.name | shorten }}</span><span class="full">{{ tag.name }}</span>
+            </span>
+            </div>
+          </td>
+        </tr>
         </tbody>
       </table>
 
@@ -70,4 +82,14 @@
   <div class="col-md-8">
     <div ui-view="document"></div>
   </div>
-</div>
\ No newline at end of file
+</div>
+
+<script type="text/ng-template" id="tag-tree-item">
+  <span class="btn" ng-style="{ 'background-color': tag.color }"></span>
+  <span class="btn btn-link" ng-click="setSearch('tag:' + tag.name)">
+    {{ tag.name }}
+  </span>
+  <ul class="list-unstyled">
+    <li ng-repeat="tag in getChildrenTags(tag.id)" ng-include="'tag-tree-item'"></li>
+  </ul>
+</script>
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/partial/docs/document.view.activity.html b/docs-web/src/main/webapp/src/partial/docs/document.view.activity.html
new file mode 100644
index 00000000..6726c5ed
--- /dev/null
+++ b/docs-web/src/main/webapp/src/partial/docs/document.view.activity.html
@@ -0,0 +1 @@
+<audit-log logs="logs" />
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/partial/docs/document.view.content.html b/docs-web/src/main/webapp/src/partial/docs/document.view.content.html
new file mode 100644
index 00000000..9e1a3021
--- /dev/null
+++ b/docs-web/src/main/webapp/src/partial/docs/document.view.content.html
@@ -0,0 +1,37 @@
+<p ng-bind-html="document.description | newline"></p>
+
+<div ng-file-drop drag-over-class="bg-success" ng-multiple="true" allow-dir="false" ng-model="dropFiles"
+     accept="image/*,application/pdf,application/zip" ng-file-change="fileDropped($files, $event, $rejectedFiles)">
+  <div class="row upload-zone" ui-sortable="fileSortableOptions" ng-model="files">
+    <div class="col-xs-6 col-sm-4 col-md-3 col-lg-2 text-center" ng-repeat="file in files">
+      <div class="thumbnail" ng-if="file.id">
+        <a ng-click="openFile(file)">
+          <img class="thumbnail-file" ng-src="../api/file/{{ file.id }}/data?size=thumb" tooltip="{{ file.mimetype }}" tooltip-placement="top" />
+        </a>
+        <div class="caption" ng-show="document.writable">
+          <div class="pull-left">
+            <div class="btn btn-default handle"><span class="glyphicon glyphicon-resize-horizontal"></span></div>
+          </div>
+          <div class="pull-right">
+            <button class="btn btn-danger" ng-click="deleteFile(file)"><span class="glyphicon glyphicon-trash"></span></button>
+          </div>
+          <div class="clearfix"></div>
+        </div>
+      </div>
+
+      <div class="thumbnail" ng-if="!file.id">
+        <p class="text-center lead">
+          {{ file.status }}
+        </p>
+        <div class="caption">
+          <progressbar value="file.progress" class="progress-info active"></progressbar>
+        </div>
+      </div>
+    </div>
+
+    <p class="text-center well-lg" ng-if="files.length == 0">
+      <span class="glyphicon glyphicon-move"></span>
+      Drag &amp; drop files here to upload
+    </p>
+  </div>
+</div>
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/partial/docs/document.view.html b/docs-web/src/main/webapp/src/partial/docs/document.view.html
index 2643b426..82a608f4 100644
--- a/docs-web/src/main/webapp/src/partial/docs/document.view.html
+++ b/docs-web/src/main/webapp/src/partial/docs/document.view.html
@@ -38,119 +38,24 @@
 	  </ul>
 	</div>
 
-  <tabset>
-    <tab>
-      <tab-heading class="pointer">
+  <ul class="nav nav-tabs">
+    <li ng-class="{ active: $state.current.name == 'document.view.content' }">
+      <a href="#/document/view/{{ document.id }}/content">
         <span class="glyphicon glyphicon-file"></span> Content
-      </tab-heading>
-
-      <p ng-bind-html="document.description | newline"></p>
-
-      <div ng-file-drop drag-over-class="bg-success" ng-multiple="true" allow-dir="false" ng-model="dropFiles"
-           accept="image/*,application/pdf,application/zip" ng-file-change="fileDropped($files, $event, $rejectedFiles)">
-        <div class="row upload-zone" ui-sortable="fileSortableOptions" ng-model="files">
-          <div class="col-xs-6 col-sm-4 col-md-3 col-lg-2 text-center" ng-repeat="file in files">
-            <div class="thumbnail" ng-if="file.id">
-              <a ng-click="openFile(file)">
-                <img class="thumbnail-file" ng-src="../api/file/{{ file.id }}/data?size=thumb" tooltip="{{ file.mimetype }}" tooltip-placement="top" />
-              </a>
-              <div class="caption" ng-show="document.writable">
-                <div class="pull-left">
-                  <div class="btn btn-default handle"><span class="glyphicon glyphicon-resize-horizontal"></span></div>
-                </div>
-                <div class="pull-right">
-                  <button class="btn btn-danger" ng-click="deleteFile(file)"><span class="glyphicon glyphicon-trash"></span></button>
-                </div>
-                <div class="clearfix"></div>
-              </div>
-            </div>
-
-            <div class="thumbnail" ng-if="!file.id">
-              <p class="text-center lead">
-                {{ file.status }}
-              </p>
-              <div class="caption">
-                <progressbar value="file.progress" class="progress-info active"></progressbar>
-              </div>
-            </div>
-          </div>
-
-          <p class="text-center well-lg" ng-if="files.length == 0">
-            <span class="glyphicon glyphicon-move"></span>
-            Drag &amp; drop files here to upload
-          </p>
-        </div>
-      </div>
-    </tab>
-
-    <tab>
-      <tab-heading class="pointer">
+      </a>
+    </li>
+    <li ng-class="{ active: $state.current.name == 'document.view.permissions' }">
+      <a href="#/document/view/{{ document.id }}/permissions">
         <span class="glyphicon glyphicon-user"></span> Permissions
-      </tab-heading>
-
-      <table class="table">
-        <tr>
-          <th style="width: 40%">For</th>
-          <th style="width: 40%">Permission</th>
-        </tr>
-
-        <tr ng-repeat="(id, acl) in acls">
-          <td><em>{{ acl[0].type == 'SHARE' ? 'Shared' : 'User' }}</em> {{ acl[0].name }}</td>
-          <td>
-            <span class="label label-default" style="margin-right: 6px;" ng-repeat="a in acl | orderBy: 'perm'">
-              {{ a.perm }}
-              <span ng-show="(document.creator != a.name && a.type == 'USER' || a.type != 'USER') && document.writable"
-                    class="glyphicon glyphicon-remove pointer"
-                    ng-click="deleteAcl(a)"></span>
-            </span>
-          </td>
-        </tr>
-      </table>
-
-      <div ng-show="document.writable">
-        <h4>Add a permission</h4>
-
-        <form name="aclForm" class="form-horizontal">
-          <div class="form-group">
-            <label class=" col-sm-2 control-label" for="inputTarget">User</label>
-            <div class="col-sm-3">
-              <input required ng-maxlength="50" class="form-control" type="text" id="inputTarget"
-                     placeholder="Type a username" name="username" ng-model="acl.username" autocomplete="off"
-                     typeahead="username for username in getTargetAclTypeahead($viewValue) | filter: $viewValue"
-                     typeahead-wait-ms="200" />
-            </div>
-          </div>
-
-          <div class="form-group">
-            <label class=" col-sm-2 control-label" for="inputPermission">Permission</label>
-            <div class="col-sm-3">
-              <select class="form-control" ng-model="acl.perm" id="inputPermission">
-                <option value="READ">Can read</option>
-                <option value="READWRITE">Can edit</option>
-              </select>
-            </div>
-          </div>
-
-          <div class="form-group">
-            <div class="col-sm-offset-2 col-sm-10">
-              <button type="submit" class="btn btn-primary"  ng-disabled="!aclForm.$valid" ng-click="addAcl()">
-                <span class="glyphicon glyphicon-plus"></span>
-                Add
-              </button>
-            </div>
-          </div>
-        </form>
-      </div>
-    </tab>
-
-    <tab>
-      <tab-heading class="pointer">
+      </a>
+    </li>
+    <li ng-class="{ active: $state.current.name == 'document.view.activity' }">
+      <a href="#/document/view/{{ document.id }}/activity">
         <span class="glyphicon glyphicon-tasks"></span> Activity
-      </tab-heading>
-
-      <audit-log logs="logs" />
-    </tab>
-  </tabset>
+      </a>
+    </li>
+  </ul>
 
+  <div ui-view="tab"></div>
 	<div ui-view="file"></div>
 </div>
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/partial/docs/document.view.permissions.html b/docs-web/src/main/webapp/src/partial/docs/document.view.permissions.html
new file mode 100644
index 00000000..c8921061
--- /dev/null
+++ b/docs-web/src/main/webapp/src/partial/docs/document.view.permissions.html
@@ -0,0 +1,53 @@
+<table class="table">
+  <tr>
+    <th style="width: 40%">For</th>
+    <th style="width: 40%">Permission</th>
+  </tr>
+
+  <tr ng-repeat="(id, acl) in acls">
+    <td><em>{{ acl[0].type == 'SHARE' ? 'Shared' : 'User' }}</em> {{ acl[0].name }}</td>
+    <td>
+            <span class="label label-default" style="margin-right: 6px;" ng-repeat="a in acl | orderBy: 'perm'">
+              {{ a.perm }}
+              <span ng-show="(document.creator != a.name && a.type == 'USER' || a.type != 'USER') && document.writable"
+                    class="glyphicon glyphicon-remove pointer"
+                    ng-click="deleteAcl(a)"></span>
+            </span>
+    </td>
+  </tr>
+</table>
+
+<div ng-show="document.writable">
+  <h4>Add a permission</h4>
+
+  <form name="aclForm" class="form-horizontal">
+    <div class="form-group">
+      <label class=" col-sm-2 control-label" for="inputTarget">User</label>
+      <div class="col-sm-3">
+        <input required ng-maxlength="50" class="form-control" type="text" id="inputTarget"
+               placeholder="Type a username" name="username" ng-model="acl.username" autocomplete="off"
+               typeahead="username for username in getTargetAclTypeahead($viewValue) | filter: $viewValue"
+               typeahead-wait-ms="200" />
+      </div>
+    </div>
+
+    <div class="form-group">
+      <label class=" col-sm-2 control-label" for="inputPermission">Permission</label>
+      <div class="col-sm-3">
+        <select class="form-control" ng-model="acl.perm" id="inputPermission">
+          <option value="READ">Can read</option>
+          <option value="READWRITE">Can edit</option>
+        </select>
+      </div>
+    </div>
+
+    <div class="form-group">
+      <div class="col-sm-offset-2 col-sm-10">
+        <button type="submit" class="btn btn-primary"  ng-disabled="!aclForm.$valid" ng-click="addAcl()">
+          <span class="glyphicon glyphicon-plus"></span>
+          Add
+        </button>
+      </div>
+    </div>
+  </form>
+</div>
\ No newline at end of file
diff --git a/docs-web/src/main/webapp/src/partial/docs/tag.html b/docs-web/src/main/webapp/src/partial/docs/tag.html
index c8f02165..37a9e7c9 100644
--- a/docs-web/src/main/webapp/src/partial/docs/tag.html
+++ b/docs-web/src/main/webapp/src/partial/docs/tag.html
@@ -21,6 +21,15 @@
         <tbody>
           <tr ng-repeat="tag in tags | filter:search">
             <td><inline-edit value="tag.name" on-edit="updateTag(tag)" /></td>
+            <td class="col-xs-4">
+              <select class="form-control" ng-model="tag.parent" ng-change="updateTag(tag)">
+                <option value="" ng-selected="!tag.parent"></option>
+                <option ng-repeat="tag0 in tags"
+                        ng-if="tag0.id != tag.id"
+                        ng-selected="tag.parent == tag0.id"
+                        value="{{ tag0.id }}">Parent: {{ tag0.name }}</option>
+              </select>
+            </td>
             <td class="col-xs-1"><span colorpicker class="btn" on-hide="updateTag(tag)" data-color="" ng-model="tag.color" ng-style="{ 'background': tag.color }">&nbsp;</span></td>
             <td class="col-xs-1"><button class="btn btn-danger pull-right" ng-click="deleteTag(tag)"><span class="glyphicon glyphicon-trash"></span></button></td>
           </tr>
diff --git a/docs-web/src/main/webapp/src/style/main.less b/docs-web/src/main/webapp/src/style/main.less
index 1ba0630a..ec55a44b 100644
--- a/docs-web/src/main/webapp/src/style/main.less
+++ b/docs-web/src/main/webapp/src/style/main.less
@@ -183,4 +183,17 @@ input[readonly].share-link {
 
 .tab-pane {
   margin-top: 20px;
+}
+
+// Tag tree
+.tag-tree-dropdown {
+  padding-left: 0;
+
+  .tag-tree {
+    li {
+      margin-left: 20px;
+      margin-top: 8px;
+      margin-bottom: 8px;
+    }
+  }
 }
\ No newline at end of file
diff --git a/docs-web/src/prod/resources/config.properties b/docs-web/src/prod/resources/config.properties
index f2362d2f..87577f48 100644
--- a/docs-web/src/prod/resources/config.properties
+++ b/docs-web/src/prod/resources/config.properties
@@ -1,3 +1,3 @@
 api.current_version=${project.version}
 api.min_version=1.0
-db.version=1
\ No newline at end of file
+db.version=2
\ No newline at end of file
diff --git a/docs-web/src/stress/resources/config.properties b/docs-web/src/stress/resources/config.properties
index f2362d2f..87577f48 100644
--- a/docs-web/src/stress/resources/config.properties
+++ b/docs-web/src/stress/resources/config.properties
@@ -1,3 +1,3 @@
 api.current_version=${project.version}
 api.min_version=1.0
-db.version=1
\ No newline at end of file
+db.version=2
\ No newline at end of file
diff --git a/docs-web/src/test/java/com/sismics/docs/rest/TestTagResource.java b/docs-web/src/test/java/com/sismics/docs/rest/TestTagResource.java
index b9fa0532..3094879a 100644
--- a/docs-web/src/test/java/com/sismics/docs/rest/TestTagResource.java
+++ b/docs-web/src/test/java/com/sismics/docs/rest/TestTagResource.java
@@ -2,6 +2,7 @@ package com.sismics.docs.rest;
 
 import javax.json.JsonArray;
 import javax.json.JsonObject;
+import javax.json.JsonValue;
 import javax.ws.rs.client.Entity;
 import javax.ws.rs.core.Form;
 import javax.ws.rs.core.Response;
@@ -44,7 +45,8 @@ public class TestTagResource extends BaseJerseyTest {
                 .cookie(TokenBasedSecurityFilter.COOKIE_NAME, tag1Token)
                 .put(Entity.form(new Form()
                         .param("name", "Tag4")
-                        .param("color", "#00ff00")), JsonObject.class);
+                        .param("color", "#00ff00")
+                        .param("parent", tag3Id)), JsonObject.class);
         String tag4Id = json.getString("id");
         Assert.assertNotNull(tag4Id);
         
@@ -129,6 +131,7 @@ public class TestTagResource extends BaseJerseyTest {
         Assert.assertTrue(tags.size() > 0);
         Assert.assertEquals("Tag4", tags.getJsonObject(1).getString("name"));
         Assert.assertEquals("#00ff00", tags.getJsonObject(1).getString("color"));
+        Assert.assertEquals(tag3Id, tags.getJsonObject(1).getString("parent"));
         
         // Update a tag
         json = target().path("/tag/" + tag4Id).request()
@@ -146,6 +149,7 @@ public class TestTagResource extends BaseJerseyTest {
         Assert.assertTrue(tags.size() > 0);
         Assert.assertEquals("UpdatedName", tags.getJsonObject(1).getString("name"));
         Assert.assertEquals("#0000ff", tags.getJsonObject(1).getString("color"));
+        Assert.assertEquals(JsonValue.NULL, tags.getJsonObject(1).get("parent"));
         
         // Deletes a tag
         target().path("/tag/" + tag4Id).request()