diff --git a/src/applications/differential/controller/DifferentialRevisionViewController.php b/src/applications/differential/controller/DifferentialRevisionViewController.php
--- a/src/applications/differential/controller/DifferentialRevisionViewController.php
+++ b/src/applications/differential/controller/DifferentialRevisionViewController.php
@@ -40,6 +40,85 @@
     return $this;
   }
 
+
+  private function getCompleteHandles(PhabricatorHandleList $handles) {
+    $phids = array();
+
+    foreach ($handles as $phid => $handle) {
+      if (!$handle->isComplete()) {
+        continue;
+      }
+      $phids[] = $phid;
+    }
+
+    return $handles->newSublist($phids);
+  }
+
+  private function newMentionsTab(
+    DifferentialRevision $revision) {
+
+    $phid = $revision->getPHID();
+
+    $edge_types = array(
+      PhabricatorObjectMentionedByObjectEdgeType::EDGECONST,
+      PhabricatorObjectMentionsObjectEdgeType::EDGECONST,
+    );
+
+    $edge_query = id(new PhabricatorEdgeQuery())
+      ->withSourcePHIDs(array($phid))
+      ->withEdgeTypes($edge_types);
+
+    $edge_query->execute();
+
+    $in_type = PhabricatorObjectMentionedByObjectEdgeType::EDGECONST;
+    $out_type = PhabricatorObjectMentionsObjectEdgeType::EDGECONST;
+
+    $in_phids = $edge_query->getDestinationPHIDs(array(), array($in_type));
+    $out_phids = $edge_query->getDestinationPHIDs(array(), array($out_type));
+
+    // Filter out any mentioned users from the list. These are not generally
+    // very interesting to show in a relationship summary since they usually
+    // end up as subscribers anyway.
+
+    $user_type = PhabricatorPeopleUserPHIDType::TYPECONST;
+    foreach ($out_phids as $key => $out_phid) {
+      if (phid_get_type($out_phid) == $user_type) {
+        unset($out_phids[$key]);
+      }
+    }
+
+    if (!$in_phids && !$out_phids) {
+      return null;
+    }
+
+    $viewer = $this->getViewer();
+    $in_handles = $viewer->loadHandles($in_phids);
+    $out_handles = $viewer->loadHandles($out_phids);
+
+    $in_handles = $this->getCompleteHandles($in_handles);
+    $out_handles = $this->getCompleteHandles($out_handles);
+
+    if (!count($in_handles) && !count($out_handles)) {
+      return null;
+    }
+
+    $view = new PHUIPropertyListView();
+
+    if (count($in_handles)) {
+      $view->addProperty(pht('Mentioned In'), $in_handles->renderList());
+    }
+
+    if (count($out_handles)) {
+      $view->addProperty(pht('Mentioned Here'), $out_handles->renderList());
+    }
+
+    return id(new PHUITabView())
+      ->setName(pht('Mentions'))
+      ->setKey('mentions')
+      ->appendChild($view);
+  }
+
+
   public function handleRequest(AphrontRequest $request) {
     $viewer = $this->getViewer();
     $this->revisionID = $request->getURIData('id');
@@ -488,6 +567,8 @@
         ->setKey('history')
         ->appendChild($history));
 
+    $tab_group->addTab($this->newMentionsTab($revision));
+
     $filetree = id(new DifferentialFileTreeEngine())
       ->setViewer($viewer);
     $filetree_collapsed = !$filetree->getIsVisible();