diff --git a/src/applications/maniphest/query/ManiphestTaskQuery.php b/src/applications/maniphest/query/ManiphestTaskQuery.php
--- a/src/applications/maniphest/query/ManiphestTaskQuery.php
+++ b/src/applications/maniphest/query/ManiphestTaskQuery.php
@@ -50,6 +50,11 @@
   const ORDER_MODIFIED      = 'order-modified';
   const ORDER_TITLE         = 'order-title';
 
+  private $hasAssignee = 'assignee-doesnt-matter';
+  const ASSIGNEE_DOESNT_MATTER = 'assignee-doesnt-matter';
+  const ASSIGNEE_YES = 'assignee-yes';
+  const ASSIGNEE_NO = 'assignee-no';
+
   const DEFAULT_PAGE_SIZE   = 1000;
 
   public function withAuthors(array $authors) {
@@ -143,6 +148,11 @@
     return $this;
   }
 
+  public function setHasAssignee($has_assignee) {
+    $this->hasAssignee = $has_assignee;
+    return $this;
+  }
+
   public function setOrderBy($order) {
     $this->orderBy = $order;
     return $this;
@@ -441,30 +451,44 @@
   }
 
   private function buildOwnerWhereClause(AphrontDatabaseConnection $conn) {
-    if (!$this->ownerPHIDs) {
-      if ($this->includeUnowned === null) {
-        return null;
-      } else if ($this->includeUnowned) {
+    if ($this->hasAssignee === self::ASSIGNEE_NO) {
+      if (!$this->ownerPHIDs) {
         return qsprintf(
           $conn,
           'ownerPHID IS NULL');
-      } else {
+      }
+      else {
+        // If user has specified a user but set "No Asignee" then the
+        // no-asignee statement takes priority, and we return a false clause
+        // causing no results at all times.
+        return qsprintf(
+          $conn,
+          '1=2');
+      }
+    }
+    else if ($this->hasAssignee === self::ASSIGNEE_YES) {
+      if (!$this->ownerPHIDs) {
         return qsprintf(
           $conn,
           'ownerPHID IS NOT NULL');
       }
+      else {
+        return qsprintf(
+          $conn,
+          'ownerPHID IN (%Ls)',
+          $this->ownerPHIDs);
+      }
     }
-
-    if ($this->includeUnowned) {
-      return qsprintf(
-        $conn,
-        'ownerPHID IN (%Ls) OR ownerPHID IS NULL',
-        $this->ownerPHIDs);
-    } else {
-      return qsprintf(
-        $conn,
-        'ownerPHID IN (%Ls)',
-        $this->ownerPHIDs);
+    else if ($this->hasAssignee === self::ASSIGNEE_DOESNT_MATTER) {
+      if (!$this->ownerPHIDs) {
+        return null;
+      }
+      else {
+        return qsprintf(
+          $conn,
+          'ownerPHID IN (%Ls)',
+          $this->ownerPHIDs);
+      }
     }
   }
 
diff --git a/src/applications/maniphest/query/ManiphestTaskSearchEngine.php b/src/applications/maniphest/query/ManiphestTaskSearchEngine.php
--- a/src/applications/maniphest/query/ManiphestTaskSearchEngine.php
+++ b/src/applications/maniphest/query/ManiphestTaskSearchEngine.php
@@ -49,8 +49,6 @@
       'assignedPHIDs',
       $this->readUsersFromRequest($request, 'assigned'));
 
-    $saved->setParameter('withUnassigned', $request->getBool('withUnassigned'));
-
     $saved->setParameter(
       'authorPHIDs',
       $this->readUsersFromRequest($request, 'authors'));
@@ -68,6 +66,7 @@
       $this->readListFromRequest($request, 'priorities'));
 
     $saved->setParameter('group', $request->getStr('group'));
+    $saved->setParameter('has_assignee', $request->getStr('has_assignee'));
     $saved->setParameter('order', $request->getStr('order'));
 
     $ids = $request->getStrList('ids');
@@ -131,14 +130,9 @@
       $query->withSubscribers($subscriber_phids);
     }
 
-    $with_unassigned = $saved->getParameter('withUnassigned');
-    if ($with_unassigned) {
-      $query->withOwners(array(null));
-    } else {
-      $assigned_phids = $saved->getParameter('assignedPHIDs', array());
-      if ($assigned_phids) {
-        $query->withOwners($assigned_phids);
-      }
+    $assigned_phids = $saved->getParameter('assignedPHIDs', array());
+    if ($assigned_phids) {
+      $query->withOwners($assigned_phids);
     }
 
     $statuses = $saved->getParameter('statuses');
@@ -167,6 +161,14 @@
       $query->setGroupBy(head($this->getGroupValues()));
     }
 
+    $has_assignee = $saved->getParameter('has_assignee');
+    $has_assignee = idx($this->getHasAssigneeValues(), $has_assignee);
+    if ($has_assignee) {
+      $query->setHasAssignee($has_assignee);
+    } else {
+      $query->setHasAssignee(head($this->getHasAssigneeValues()));
+    }
+
     $ids = $saved->getParameter('ids');
     if ($ids) {
       $query->withIDs($ids);
@@ -277,7 +279,6 @@
     $user_project_handles = array_select_keys($handles, $user_project_phids);
     $subscriber_handles = array_select_keys($handles, $subscriber_phids);
 
-    $with_unassigned = $saved->getParameter('withUnassigned');
     $with_no_projects = $saved->getParameter('withNoProject');
 
     $statuses = $saved->getParameter('statuses', array());
@@ -314,13 +315,6 @@
           ->setLabel(pht('Assigned To'))
           ->setValue($assigned_handles))
       ->appendChild(
-        id(new AphrontFormCheckboxControl())
-          ->addCheckbox(
-            'withUnassigned',
-            1,
-            pht('Show only unassigned tasks.'),
-            $with_unassigned))
-      ->appendChild(
         id(new AphrontFormTokenizerControl())
           ->setDatasource(new PhabricatorProjectDatasource())
           ->setName('allProjects')
@@ -387,6 +381,13 @@
             ->setValue($saved->getParameter('order'))
             ->setOptions($this->getOrderOptions()));
     }
+    $form
+    ->appendChild(
+      id(new AphrontFormSelectControl())
+      ->setName('has_assignee')
+      ->setLabel(pht('Has Assignee'))
+      ->setValue($saved->getParameter('has_assignee'))
+      ->setOptions($this->getHasAssigneeOptions()));
 
     $form
       ->appendChild(
@@ -515,6 +516,22 @@
     );
   }
 
+  private function getHasAssigneeOptions() {
+    return array(
+      'doesnt_matter' => pht('Doesn\'t Matter'),
+      'yes' => pht('Yes'),
+      'no' => pht('No')
+    );
+  }
+
+  private function getHasAssigneeValues () {
+    return array(
+      'doesnt_matter' => ManiphestTaskQuery::ASSIGNEE_DOESNT_MATTER,
+      'yes' => ManiphestTaskQuery::ASSIGNEE_YES,
+      'no'   => ManiphestTaskQuery::ASSIGNEE_NO
+    );
+  }
+
   private function getGroupValues() {
     return array(
       'priority' => ManiphestTaskQuery::GROUP_PRIORITY,