diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -3514,6 +3514,7 @@
     'PhabricatorProjectWatcherListView' => 'applications/project/view/PhabricatorProjectWatcherListView.php',
     'PhabricatorProjectWorkboardBackgroundColor' => 'applications/project/constants/PhabricatorProjectWorkboardBackgroundColor.php',
     'PhabricatorProjectWorkboardProfileMenuItem' => 'applications/project/menuitem/PhabricatorProjectWorkboardProfileMenuItem.php',
+    'PhabricatorProjectsAncestorsSearchEngineAttachment' => 'applications/project/engineextension/PhabricatorProjectsAncestorsSearchEngineAttachment.php',
     'PhabricatorProjectsCurtainExtension' => 'applications/project/engineextension/PhabricatorProjectsCurtainExtension.php',
     'PhabricatorProjectsEditEngineExtension' => 'applications/project/engineextension/PhabricatorProjectsEditEngineExtension.php',
     'PhabricatorProjectsEditField' => 'applications/transactions/editfield/PhabricatorProjectsEditField.php',
@@ -8666,6 +8667,7 @@
     'PhabricatorProjectWatcherListView' => 'PhabricatorProjectUserListView',
     'PhabricatorProjectWorkboardBackgroundColor' => 'Phobject',
     'PhabricatorProjectWorkboardProfileMenuItem' => 'PhabricatorProfileMenuItem',
+    'PhabricatorProjectsAncestorsSearchEngineAttachment' => 'PhabricatorSearchEngineAttachment',
     'PhabricatorProjectsCurtainExtension' => 'PHUICurtainExtension',
     'PhabricatorProjectsEditEngineExtension' => 'PhabricatorEditEngineExtension',
     'PhabricatorProjectsEditField' => 'PhabricatorTokenizerEditField',
diff --git a/src/applications/project/engineextension/PhabricatorProjectsAncestorsSearchEngineAttachment.php b/src/applications/project/engineextension/PhabricatorProjectsAncestorsSearchEngineAttachment.php
new file mode 100644
--- /dev/null
+++ b/src/applications/project/engineextension/PhabricatorProjectsAncestorsSearchEngineAttachment.php
@@ -0,0 +1,30 @@
+<?php
+
+final class PhabricatorProjectsAncestorsSearchEngineAttachment
+  extends PhabricatorSearchEngineAttachment {
+
+  public function getAttachmentName() {
+    return pht('Project Ancestors');
+  }
+
+  public function getAttachmentDescription() {
+    return pht('Get the full ancestor list for each project.');
+  }
+
+  public function getAttachmentForObject($object, $data, $spec) {
+    $ancestors = $object->getAncestorProjects();
+
+    // Order ancestors by depth, ascending.
+    $ancestors = array_reverse($ancestors);
+
+    $results = array();
+    foreach ($ancestors as $ancestor) {
+      $results[] = $ancestor->getRefForConduit();
+    }
+
+    return array(
+      'ancestors' => $results,
+    );
+  }
+
+}
diff --git a/src/applications/project/storage/PhabricatorProject.php b/src/applications/project/storage/PhabricatorProject.php
--- a/src/applications/project/storage/PhabricatorProject.php
+++ b/src/applications/project/storage/PhabricatorProject.php
@@ -746,6 +746,20 @@
         ->setType('int?')
         ->setDescription(pht('For milestones, milestone sequence number.')),
       id(new PhabricatorConduitSearchFieldSpecification())
+        ->setKey('parent')
+        ->setType('map<string, wild>?')
+        ->setDescription(
+          pht(
+            'For subprojects and milestones, a brief description of the '.
+            'parent project.')),
+      id(new PhabricatorConduitSearchFieldSpecification())
+        ->setKey('depth')
+        ->setType('int')
+        ->setDescription(
+          pht(
+            'For subprojects and milestones, depth of this project in the '.
+            'tree. Root projects have depth 0.')),
+      id(new PhabricatorConduitSearchFieldSpecification())
         ->setKey('icon')
         ->setType('map<string, wild>')
         ->setDescription(pht('Information about the project icon.')),
@@ -766,10 +780,19 @@
       $milestone = null;
     }
 
+    $parent = $this->getParentProject();
+    if ($parent) {
+      $parent_ref = $parent->getRefForConduit();
+    } else {
+      $parent_ref = null;
+    }
+
     return array(
       'name' => $this->getName(),
       'slug' => $this->getPrimarySlug(),
       'milestone' => $milestone,
+      'depth' => (int)$this->getProjectDepth(),
+      'parent' => $parent_ref,
       'icon' => array(
         'key' => $this->getDisplayIconKey(),
         'name' => $this->getDisplayIconName(),
@@ -788,6 +811,20 @@
         ->setAttachmentKey('members'),
       id(new PhabricatorProjectsWatchersSearchEngineAttachment())
         ->setAttachmentKey('watchers'),
+      id(new PhabricatorProjectsAncestorsSearchEngineAttachment())
+        ->setAttachmentKey('ancestors'),
+    );
+  }
+
+  /**
+   * Get an abbreviated representation of this project for use in providing
+   * "parent" and "ancestor" information.
+   */
+  public function getRefForConduit() {
+    return array(
+      'id' => (int)$this->getID(),
+      'phid' => $this->getPHID(),
+      'name' => $this->getName(),
     );
   }