diff --git a/includes/t-data/dao_tasks.inc.php b/includes/t-data/dao_tasks.inc.php
index 796f0c1..301c922 100644
--- a/includes/t-data/dao_tasks.inc.php
+++ b/includes/t-data/dao_tasks.inc.php
@@ -98,6 +98,27 @@ class DAO_Tasks
 			.		'INNER JOIN users u USING (user_id) '
 			.	'WHERE n.task_id = $1 '
 			.	'ORDER BY n.note_added DESC' )->execute( $id );
+		$task->dependencies = $this->query(
+			'SELECT t.task_id AS id , t.task_title AS title , t.item_id AS item , '
+			.		'i.item_name AS item_name , '
+			.		'( ct.completed_task_time IS NOT NULL ) AS completed '
+			.	'FROM task_dependencies td '
+			.		'INNER JOIN tasks t ON t.task_id = td.task_id_depends '
+			.		'INNER JOIN items i USING ( item_id ) '
+			.		'LEFT OUTER JOIN completed_tasks ct ON ct.task_id = t.task_id '
+			.	'WHERE td.task_id = $1 '
+			.	'ORDER BY i.item_name , t.task_priority , t.task_title' )->execute( $id );
+		$task->reverseDependencies = $this->query(
+			'SELECT t.task_id AS id , t.task_title AS title , t.item_id AS item , '
+			.		'i.item_name AS item_name , '
+			.		'( ct.completed_task_time IS NOT NULL ) AS completed '
+			.	'FROM task_dependencies td '
+			.		'INNER JOIN tasks t USING( task_id ) '
+			.		'INNER JOIN items i USING ( item_id ) '
+			.		'LEFT OUTER JOIN completed_tasks ct USING ( task_id ) '
+			.	'WHERE td.task_id_depends = $1 '
+			.	'ORDER BY i.item_name , t.task_priority , t.task_title' )->execute( $id );
+
 		return $task;
 	}
 
@@ -113,6 +134,30 @@ class DAO_Tasks
 	}
 
 
+	public function canFinish( $task )
+	{
+		assert( $task->completed_at == null );
+		foreach ( $task->dependencies as $dependency ) {
+			if ( $dependency->completed != 't' ) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+
+	public function canRestart( $task )
+	{
+		assert( $task->completed_at != null );
+		foreach ( $task->reverseDependencies as $dependency ) {
+			if ( $dependency->completed == 't' ) {
+				return false;
+			}
+		}
+		return true;
+	}
+
+
 	public function delete( $task )
 	{
 		$this->query( 'DELETE FROM tasks WHERE task_id = $1' )->execute( $task );
diff --git a/includes/t-tasks/controllers.inc.php b/includes/t-tasks/controllers.inc.php
index 12bc91d..4f3108f 100644
--- a/includes/t-tasks/controllers.inc.php
+++ b/includes/t-tasks/controllers.inc.php
@@ -66,15 +66,20 @@ class Ctrl_TaskDetails
 		$items->getLineage( $this->task->item = $items->get( $this->task->item ) );
 
 		$box = Loader::View( 'box' , $bTitle , Loader::View( 'task_details' , $this->task ) );
+
+		$tasks = Loader::DAO( 'tasks' );
 		if ( $this->task->completed_by === null ) {
 			$box->addButton( BoxButton::create( 'Edit task' , 'tasks/edit?id=' . $this->task->id )
-					->setClass( 'icon edit' ) )
-				->addButton( BoxButton::create( 'Mark as completed' ,
-						'tasks/finish?id=' . $this->task->id )
-					->setClass( 'icon stop' ) );
+					->setClass( 'icon edit' ) );
+			if ( $tasks->canFinish( $this->task ) ) {
+				$box->addButton( BoxButton::create( 'Mark as completed' , 'tasks/finish?id=' . $this->task->id )
+						->setClass( 'icon stop' ) );
+			};
 		} else {
-			$box->addButton( BoxButton::create( 'Re-activate' , 'tasks/restart?id=' . $this->task->id )
+			if ( $tasks->canRestart( $this->task ) ) {
+				$box->addButton( BoxButton::create( 'Re-activate' , 'tasks/restart?id=' . $this->task->id )
 					->setClass( 'icon start' ) );
+			}
 			$timestamp = strtotime( $this->task->completed_at );
 		}
 
@@ -88,6 +93,34 @@ class Ctrl_TaskDetails
 }
 
 
+class Ctrl_TaskDependencies
+	extends Controller
+{
+	private $task;
+
+	public function __construct( $task )
+	{
+		$this->task = $task;
+	}
+
+
+	public function handle( Page $page )
+	{
+		$views = array(
+			Loader::View( 'box' , 'Dependencies' ,
+				Loader::View( 'task_dependencies' , $this->task , false ) )
+		);
+
+		if ( ! empty( $this->task->reverseDependencies ) ) {
+			array_push( $views , Loader::View( 'box' , 'Reverse dependencies' ,
+				Loader::View( 'task_dependencies' , $this->task , true ) ) );
+		}
+
+		return $views;
+	}
+}
+
+
 class Ctrl_TaskNotes
 	extends Controller
 {
@@ -161,9 +194,9 @@ class Ctrl_ToggleTask
 			return 'tasks';
 		}
 
-		if ( $this->isRestart ) {
+		if ( $this->isRestart && $tasks->canRestart( $task ) ) {
 			$tasks->restart( $id , '[AUTO] Task re-activated.' );
-		} else {
+		} else if ( ! $this->isRestart && $tasks->canFinish( $task ) ) {
 			$tasks->finish( $id , '[AUTO] Task completed.' );
 		}
 
diff --git a/includes/t-tasks/package.inc.php b/includes/t-tasks/package.inc.php
index b0092d8..7c63925 100644
--- a/includes/t-tasks/package.inc.php
+++ b/includes/t-tasks/package.inc.php
@@ -22,6 +22,7 @@ $package[ 'ctrls' ][] = 'edit_note_form';
 $package[ 'ctrls' ][] = 'edit_note';
 $package[ 'ctrls' ][] = 'edit_task_form';
 $package[ 'ctrls' ][] = 'edit_task';
+$package[ 'ctrls' ][] = 'task_dependencies';
 $package[ 'ctrls' ][] = 'task_details';
 $package[ 'ctrls' ][] = 'task_notes';
 $package[ 'ctrls' ][] = 'toggle_task';
@@ -31,5 +32,6 @@ $package[ 'views' ][] = 'all_tasks';
 $package[ 'views' ][] = 'tasks';
 $package[ 'views' ][] = 'task_details';
 $package[ 'views' ][] = 'task_note';
+$package[ 'views' ][] = 'task_dependencies';
 
 $package[ 'pages' ][] = 'tasks_tasks';
diff --git a/includes/t-tasks/page_controllers.inc.php b/includes/t-tasks/page_controllers.inc.php
index 858f03a..a2e9495 100644
--- a/includes/t-tasks/page_controllers.inc.php
+++ b/includes/t-tasks/page_controllers.inc.php
@@ -150,7 +150,10 @@ class Ctrl_ViewTask
 		}
 		$page->setTitle( $task->title . ' (task)' );
 
-		$result = array( Loader::Ctrl( 'task_details' , $task ) );
+		$result = array(
+			Loader::Ctrl( 'task_details' , $task ) ,
+			Loader::Ctrl( 'task_dependencies' , $task ) ,
+		);
 
 		if ( $task->completed_by === null ) {
 			array_push( $result , Loader::Ctrl( 'add_task_note_form' , $task ) );
diff --git a/includes/t-tasks/views.inc.php b/includes/t-tasks/views.inc.php
index 09fabea..c81ccff 100644
--- a/includes/t-tasks/views.inc.php
+++ b/includes/t-tasks/views.inc.php
@@ -272,7 +272,7 @@ class View_TaskNote
 
 
 class View_TaskDependencies
-	implements View
+	extends BaseURLAwareView
 {
 	private $task;
 	private $reverse;
@@ -286,16 +286,35 @@ class View_TaskDependencies
 	public function render( )
 	{
 		$source = $this->reverse ? 'reverseDependencies' : 'dependencies';
+		if ( empty( $this->task->$source ) ) {
+			return HTML::make( 'div' )
+				->setAttribute( 'class' , 'no-table' )
+				->appendText( 'This task has no dependencies.' );
+		}
+
 		$list = HTML::make( 'ul' )->setAttribute( 'class' , 'dep-list' );
+		$prevItem = null;
+		$itemList = null;
 		foreach ( $this->task->$source as $dependency ) {
+			if ( $prevItem !== $dependency->item ) {
+				$itemList = HTML::make( 'ul' );
+				$list->appendElement( HTML::make( 'li' )
+					->appendText( 'In ' )
+					->appendElement( HTML::make( 'a' )
+						->setAttribute( 'href' , $this->base . '/items/view?id=' . $dependency->item )
+						->appendText( $dependency->item_name ) )
+					->appendElement( $itemList ) );
+				$prevItem = $dependency->item;
+			}
 			$link = HTML::make( 'a' )
-				->setAttribute( 'href' , 'tasks/view?id=' . $dependency->id )
+				->setAttribute( 'href' , $this->base . '/tasks/view?id=' . $dependency->id )
 				->appendText( $dependency->title );
 			if ( ! $this->reverse ) {
 				$link->setAttribute( 'class' , ( $dependency->completed == 't' )
 					? 'satisfied' : 'missing' );
 			}
-			$list->appendElement( HTML::make( 'li' )->appendElement( $link ) );
+			$itemList->appendElement( HTML::make( 'li' )->appendElement( $link ) );
 		}
+		return $list;
 	}
 }
diff --git a/site/style.css b/site/style.css
index 7f17d98..e5dc4f6 100644
--- a/site/style.css
+++ b/site/style.css
@@ -393,3 +393,11 @@ dl.tasks dt.sub-title.completed {
 	color: #bfbfbf;
 	text-shadow: 1px 1px 2px #3f3f3f;
 }
+
+ul.dep-list a.missing {
+	color: red;
+}
+
+ul.dep-list a.satisfied {
+	color: green;
+}