diff --git a/resources/celerity/map.php b/resources/celerity/map.php
--- a/resources/celerity/map.php
+++ b/resources/celerity/map.php
@@ -412,7 +412,7 @@
     'rsrc/js/application/phortune/phortune-credit-card-form.js' => 'd12d214f',
     'rsrc/js/application/policy/behavior-policy-control.js' => '0eaa33a9',
     'rsrc/js/application/policy/behavior-policy-rule-editor.js' => '9347f172',
-    'rsrc/js/application/projects/WorkboardBoard.js' => '75727403',
+    'rsrc/js/application/projects/WorkboardBoard.js' => 'b46d88c5',
     'rsrc/js/application/projects/WorkboardCard.js' => '0392a5d8',
     'rsrc/js/application/projects/WorkboardCardTemplate.js' => '84f82dad',
     'rsrc/js/application/projects/WorkboardColumn.js' => 'c3d24e63',
@@ -743,7 +743,7 @@
     'javelin-view-renderer' => '9aae2b66',
     'javelin-view-visitor' => '308f9fe4',
     'javelin-websocket' => 'fdc13e4e',
-    'javelin-workboard-board' => '75727403',
+    'javelin-workboard-board' => 'b46d88c5',
     'javelin-workboard-card' => '0392a5d8',
     'javelin-workboard-card-template' => '84f82dad',
     'javelin-workboard-column' => 'c3d24e63',
@@ -1549,18 +1549,6 @@
       'javelin-uri',
       'javelin-request',
     ),
-    75727403 => array(
-      'javelin-install',
-      'javelin-dom',
-      'javelin-util',
-      'javelin-stratcom',
-      'javelin-workflow',
-      'phabricator-draggable-list',
-      'javelin-workboard-column',
-      'javelin-workboard-header-template',
-      'javelin-workboard-card-template',
-      'javelin-workboard-order-template',
-    ),
     '78bc5d94' => array(
       'javelin-behavior',
       'javelin-uri',
@@ -1900,6 +1888,18 @@
     'b347a301' => array(
       'javelin-behavior',
     ),
+    'b46d88c5' => array(
+      'javelin-install',
+      'javelin-dom',
+      'javelin-util',
+      'javelin-stratcom',
+      'javelin-workflow',
+      'phabricator-draggable-list',
+      'javelin-workboard-column',
+      'javelin-workboard-header-template',
+      'javelin-workboard-card-template',
+      'javelin-workboard-order-template',
+    ),
     'b49fd60c' => array(
       'multirow-row-manager',
       'trigger-rule',
diff --git a/src/applications/maniphest/editor/ManiphestTransactionEditor.php b/src/applications/maniphest/editor/ManiphestTransactionEditor.php
--- a/src/applications/maniphest/editor/ManiphestTransactionEditor.php
+++ b/src/applications/maniphest/editor/ManiphestTransactionEditor.php
@@ -3,6 +3,7 @@
 final class ManiphestTransactionEditor
   extends PhabricatorApplicationTransactionEditor {
 
+  private $oldProjectPHIDs;
   private $moreValidationErrors = array();
 
   public function getEditorApplicationClass() {
@@ -378,6 +379,11 @@
       }
     }
 
+    $send_notifications = PhabricatorNotificationClient::isEnabled();
+    if ($send_notifications) {
+      $this->oldProjectPHIDs = $this->loadProjectPHIDs($object);
+    }
+
     return $results;
   }
 
@@ -859,14 +865,61 @@
     return array_values($phid_list);
   }
 
-
   protected function didApplyTransactions($object, array $xactions) {
-    // TODO: This should include projects which the object was previously
-    // associated with but no longer is (so it can be removed from those
-    // boards) but currently does not.
+    $send_notifications = PhabricatorNotificationClient::isEnabled();
+    if ($send_notifications) {
+      $old_phids = $this->oldProjectPHIDs;
+      $new_phids = $this->loadProjectPHIDs($object);
+
+      // We want to emit update notifications for all old and new tagged
+      // projects, and all parents of those projects. For example, if an
+      // edit removes project "A > B" from a task, the "A" workboard should
+      // receive an update event.
+
+      $project_phids = array_fuse($old_phids) + array_fuse($new_phids);
+      $project_phids = array_keys($project_phids);
+
+      $projects = id(new PhabricatorProjectQuery())
+        ->setViewer(PhabricatorUser::getOmnipotentUser())
+        ->withPHIDs($project_phids)
+        ->execute();
+
+      $notify_projects = array();
+      foreach ($projects as $project) {
+        $notify_projects[$project->getPHID()] = $project;
+        foreach ($project->getAncestorProjects() as $ancestor) {
+          $notify_projects[$ancestor->getPHID()] = $ancestor;
+        }
+      }
+
+      foreach ($notify_projects as $key => $project) {
+        if (!$project->getHasWorkboard()) {
+          unset($notify_projects[$key]);
+        }
+      }
+
+      $notify_phids = array_keys($notify_projects);
+
+      if ($notify_phids) {
+        $data = array(
+          'type' => 'workboards',
+          'subscribers' => $notify_phids,
+        );
+
+        PhabricatorNotificationClient::tryToPostMessage($data);
+      }
+    }
+
+    return $xactions;
+  }
+
+  private function loadProjectPHIDs(ManiphestTask $task) {
+    if (!$task->getPHID()) {
+      return array();
+    }
 
     $edge_query = id(new PhabricatorEdgeQuery())
-      ->withSourcePHIDs(array($object->getPHID()))
+      ->withSourcePHIDs(array($task->getPHID()))
       ->withEdgeTypes(
         array(
           PhabricatorProjectObjectHasProjectEdgeType::EDGECONST,
@@ -874,18 +927,7 @@
 
     $edge_query->execute();
 
-    $project_phids = $edge_query->getDestinationPHIDs();
-
-    if ($project_phids) {
-      $data = array(
-        'type' => 'workboards',
-        'subscribers' => $project_phids,
-      );
-
-      PhabricatorNotificationClient::tryToPostMessage($data);
-    }
-
-    return $xactions;
+    return $edge_query->getDestinationPHIDs();
   }
 
 }
diff --git a/src/applications/notification/client/PhabricatorNotificationClient.php b/src/applications/notification/client/PhabricatorNotificationClient.php
--- a/src/applications/notification/client/PhabricatorNotificationClient.php
+++ b/src/applications/notification/client/PhabricatorNotificationClient.php
@@ -37,4 +37,8 @@
     }
   }
 
+  public static function isEnabled() {
+    return (bool)PhabricatorNotificationServerRef::getEnabledAdminServers();
+  }
+
 }
diff --git a/webroot/rsrc/js/application/projects/WorkboardBoard.js b/webroot/rsrc/js/application/projects/WorkboardBoard.js
--- a/webroot/rsrc/js/application/projects/WorkboardBoard.js
+++ b/webroot/rsrc/js/application/projects/WorkboardBoard.js
@@ -711,7 +711,7 @@
           // Compare the server state to the client state, and add or remove
           // cards on the client as necessary to synchronize them.
 
-          if (update_map[card_phid][column_phid]) {
+          if (update_map[card_phid] && update_map[card_phid][column_phid]) {
             if (!card) {
               column.newCard(card_phid);
               column.markForRedraw();