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
@@ -2498,8 +2498,10 @@
     'PhabricatorSearchCheckboxesField' => 'applications/search/field/PhabricatorSearchCheckboxesField.php',
     'PhabricatorSearchConfigOptions' => 'applications/search/config/PhabricatorSearchConfigOptions.php',
     'PhabricatorSearchController' => 'applications/search/controller/PhabricatorSearchController.php',
+    'PhabricatorSearchCustomFieldProxyField' => 'applications/search/field/PhabricatorSearchCustomFieldProxyField.php',
     'PhabricatorSearchDAO' => 'applications/search/storage/PhabricatorSearchDAO.php',
     'PhabricatorSearchDatasource' => 'applications/search/typeahead/PhabricatorSearchDatasource.php',
+    'PhabricatorSearchDatasourceField' => 'applications/search/field/PhabricatorSearchDatasourceField.php',
     'PhabricatorSearchDateField' => 'applications/search/field/PhabricatorSearchDateField.php',
     'PhabricatorSearchDeleteController' => 'applications/search/controller/PhabricatorSearchDeleteController.php',
     'PhabricatorSearchDocument' => 'applications/search/storage/document/PhabricatorSearchDocument.php',
@@ -2518,13 +2520,16 @@
     'PhabricatorSearchManagementInitWorkflow' => 'applications/search/management/PhabricatorSearchManagementInitWorkflow.php',
     'PhabricatorSearchManagementWorkflow' => 'applications/search/management/PhabricatorSearchManagementWorkflow.php',
     'PhabricatorSearchOrderController' => 'applications/search/controller/PhabricatorSearchOrderController.php',
+    'PhabricatorSearchOwnersField' => 'applications/search/field/PhabricatorSearchOwnersField.php',
     'PhabricatorSearchPreferencesSettingsPanel' => 'applications/settings/panel/PhabricatorSearchPreferencesSettingsPanel.php',
     'PhabricatorSearchProjectsField' => 'applications/search/field/PhabricatorSearchProjectsField.php',
     'PhabricatorSearchRelationship' => 'applications/search/constants/PhabricatorSearchRelationship.php',
     'PhabricatorSearchResultView' => 'applications/search/view/PhabricatorSearchResultView.php',
     'PhabricatorSearchSelectController' => 'applications/search/controller/PhabricatorSearchSelectController.php',
+    'PhabricatorSearchSelectField' => 'applications/search/field/PhabricatorSearchSelectField.php',
     'PhabricatorSearchSpacesField' => 'applications/search/field/PhabricatorSearchSpacesField.php',
     'PhabricatorSearchStringListField' => 'applications/search/field/PhabricatorSearchStringListField.php',
+    'PhabricatorSearchTextField' => 'applications/search/field/PhabricatorSearchTextField.php',
     'PhabricatorSearchThreeStateField' => 'applications/search/field/PhabricatorSearchThreeStateField.php',
     'PhabricatorSearchTokenizerField' => 'applications/search/field/PhabricatorSearchTokenizerField.php',
     'PhabricatorSearchUsersField' => 'applications/search/field/PhabricatorSearchUsersField.php',
@@ -5998,8 +6003,10 @@
     'PhabricatorSearchCheckboxesField' => 'PhabricatorSearchField',
     'PhabricatorSearchConfigOptions' => 'PhabricatorApplicationConfigOptions',
     'PhabricatorSearchController' => 'PhabricatorSearchBaseController',
+    'PhabricatorSearchCustomFieldProxyField' => 'PhabricatorSearchField',
     'PhabricatorSearchDAO' => 'PhabricatorLiskDAO',
     'PhabricatorSearchDatasource' => 'PhabricatorTypeaheadCompositeDatasource',
+    'PhabricatorSearchDatasourceField' => 'PhabricatorSearchTokenizerField',
     'PhabricatorSearchDateField' => 'PhabricatorSearchField',
     'PhabricatorSearchDeleteController' => 'PhabricatorSearchBaseController',
     'PhabricatorSearchDocument' => 'PhabricatorSearchDAO',
@@ -6016,12 +6023,15 @@
     'PhabricatorSearchManagementInitWorkflow' => 'PhabricatorSearchManagementWorkflow',
     'PhabricatorSearchManagementWorkflow' => 'PhabricatorManagementWorkflow',
     'PhabricatorSearchOrderController' => 'PhabricatorSearchBaseController',
+    'PhabricatorSearchOwnersField' => 'PhabricatorSearchTokenizerField',
     'PhabricatorSearchPreferencesSettingsPanel' => 'PhabricatorSettingsPanel',
     'PhabricatorSearchProjectsField' => 'PhabricatorSearchTokenizerField',
     'PhabricatorSearchResultView' => 'AphrontView',
     'PhabricatorSearchSelectController' => 'PhabricatorSearchBaseController',
+    'PhabricatorSearchSelectField' => 'PhabricatorSearchField',
     'PhabricatorSearchSpacesField' => 'PhabricatorSearchTokenizerField',
     'PhabricatorSearchStringListField' => 'PhabricatorSearchField',
+    'PhabricatorSearchTextField' => 'PhabricatorSearchField',
     'PhabricatorSearchThreeStateField' => 'PhabricatorSearchField',
     'PhabricatorSearchTokenizerField' => 'PhabricatorSearchField',
     'PhabricatorSearchUsersField' => 'PhabricatorSearchTokenizerField',
diff --git a/src/applications/project/query/PhabricatorProjectSearchEngine.php b/src/applications/project/query/PhabricatorProjectSearchEngine.php
--- a/src/applications/project/query/PhabricatorProjectSearchEngine.php
+++ b/src/applications/project/query/PhabricatorProjectSearchEngine.php
@@ -11,131 +11,64 @@
     return 'PhabricatorProjectApplication';
   }
 
-  public function getCustomFieldObject() {
+  public function newResultObject() {
     return new PhabricatorProject();
   }
 
-  public function buildSavedQueryFromRequest(AphrontRequest $request) {
-    $saved = new PhabricatorSavedQuery();
-
-    $saved->setParameter(
-      'memberPHIDs',
-      $this->readUsersFromRequest($request, 'members'));
-
-    $saved->setParameter('status', $request->getStr('status'));
-    $saved->setParameter('name', $request->getStr('name'));
-
-    $saved->setParameter(
-      'icons',
-      $this->readListFromRequest($request, 'icons'));
-
-    $saved->setParameter(
-      'colors',
-      $this->readListFromRequest($request, 'colors'));
-
-    $this->readCustomFieldsFromRequest($request, $saved);
-
-    return $saved;
+  protected function buildCustomSearchFields() {
+    return array(
+      id(new PhabricatorSearchTextField())
+        ->setLabel(pht('Name'))
+        ->setKey('name'),
+      id(new PhabricatorSearchUsersField())
+        ->setLabel(pht('Members'))
+        ->setKey('memberPHIDs')
+        ->setAliases(array('member', 'members')),
+      id(new PhabricatorSearchSelectField())
+        ->setLabel(pht('Status'))
+        ->setKey('status')
+        ->setOptions($this->getStatusOptions()),
+      id(new PhabricatorSearchCheckboxesField())
+        ->setLabel(pht('Icons'))
+        ->setKey('icons')
+        ->setOptions($this->getIconOptions()),
+      id(new PhabricatorSearchCheckboxesField())
+        ->setLabel(pht('Colors'))
+        ->setKey('colors')
+        ->setOptions($this->getColorOptions()),
+    );
   }
 
-  public function buildQueryFromSavedQuery(PhabricatorSavedQuery $saved) {
+
+  public function buildQueryFromParameters(array $map) {
     $query = id(new PhabricatorProjectQuery())
       ->needImages(true);
 
-    $member_phids = $saved->getParameter('memberPHIDs', array());
-    if ($member_phids && is_array($member_phids)) {
-      $query->withMemberPHIDs($member_phids);
-    }
-
-    $status = $saved->getParameter('status');
-    $status = idx($this->getStatusValues(), $status);
-    if ($status) {
-      $query->withStatus($status);
-    }
-
-    $name = $saved->getParameter('name');
-    if (strlen($name)) {
-      $tokens = PhabricatorTypeaheadDatasource::tokenizeString($name);
+    if (strlen($map['name'])) {
+      $tokens = PhabricatorTypeaheadDatasource::tokenizeString($map['name']);
       $query->withNameTokens($tokens);
     }
 
-    $icons = $saved->getParameter('icons');
-    if ($icons) {
-      $query->withIcons($icons);
+    if ($map['memberPHIDs']) {
+      $query->withMemberPHIDs($map['memberPHIDs']);
     }
 
-    $colors = $saved->getParameter('colors');
-    if ($colors) {
-      $query->withColors($colors);
+    if ($map['status']) {
+      $status = idx($this->getStatusValues(), $map['status']);
+      if ($status) {
+        $query->withStatus($status);
+      }
     }
 
-    $this->applyCustomFieldsToQuery($query, $saved);
-
-    return $query;
-  }
-
-  public function buildSearchForm(
-    AphrontFormView $form,
-    PhabricatorSavedQuery $saved) {
-
-    $member_phids = $saved->getParameter('memberPHIDs', array());
-
-    $status = $saved->getParameter('status');
-    $name_match = $saved->getParameter('name');
-
-    $icons = array_fuse($saved->getParameter('icons', array()));
-    $colors = array_fuse($saved->getParameter('colors', array()));
-
-    $icon_control = id(new AphrontFormCheckboxControl())
-      ->setLabel(pht('Icons'));
-    foreach (PhabricatorProjectIcon::getIconMap() as $icon => $name) {
-      $image = id(new PHUIIconView())
-        ->setIconFont($icon);
-
-      $icon_control->addCheckbox(
-        'icons[]',
-        $icon,
-        array($image, ' ', $name),
-        isset($icons[$icon]));
+    if ($map['icons']) {
+      $query->withIcons($map['icons']);
     }
 
-    $color_control = id(new AphrontFormCheckboxControl())
-      ->setLabel(pht('Colors'));
-    foreach (PhabricatorProjectIcon::getColorMap() as $color => $name) {
-      $tag = id(new PHUITagView())
-        ->setType(PHUITagView::TYPE_SHADE)
-        ->setShade($color)
-        ->setName($name);
-
-      $color_control->addCheckbox(
-        'colors[]',
-        $color,
-        $tag,
-        isset($colors[$color]));
+    if ($map['colors']) {
+      $query->withColors($map['colors']);
     }
 
-    $form
-      ->appendChild(
-        id(new AphrontFormTextControl())
-          ->setName('name')
-          ->setLabel(pht('Name'))
-          ->setValue($name_match))
-      ->appendControl(
-        id(new AphrontFormTokenizerControl())
-          ->setDatasource(new PhabricatorPeopleDatasource())
-          ->setName('members')
-          ->setLabel(pht('Members'))
-          ->setValue($member_phids))
-      ->appendChild(
-        id(new AphrontFormSelectControl())
-          ->setLabel(pht('Status'))
-          ->setName('status')
-          ->setOptions($this->getStatusOptions())
-          ->setValue($status))
-      ->appendChild($icon_control)
-      ->appendChild($color_control);
-
-    $this->appendCustomFieldsToForm($form, $saved);
+    return $query;
   }
 
   protected function getURI($path) {
@@ -192,14 +125,36 @@
     );
   }
 
-  private function getColorValues() {}
+  private function getIconOptions() {
+    $options = array();
 
-  private function getIconValues() {}
+    foreach (PhabricatorProjectIcon::getIconMap() as $icon => $name) {
+      $options[$icon] = array(
+        id(new PHUIIconView())
+          ->setIconFont($icon),
+        ' ',
+        $name,
+      );
+    }
 
-  protected function getRequiredHandlePHIDsForResultList(
-    array $projects,
-    PhabricatorSavedQuery $query) {
-    return mpull($projects, 'getPHID');
+    return $options;
+  }
+
+  private function getColorOptions() {
+    $options = array();
+
+    foreach (PhabricatorProjectIcon::getColorMap() as $color => $name) {
+      $options[$color] = array(
+        id(new PHUITagView())
+          ->setType(PHUITagView::TYPE_SHADE)
+          ->setShade($color)
+          ->setName($name),
+        ' ',
+        $name,
+      );
+    }
+
+    return $options;
   }
 
   protected function renderResultList(
@@ -208,6 +163,7 @@
     array $handles) {
     assert_instances_of($projects, 'PhabricatorProject');
     $viewer = $this->requireViewer();
+    $handles = $viewer->loadHandles(mpull($projects, 'getPHID'));
 
     $list = new PHUIObjectItemListView();
     $list->setUser($viewer);
diff --git a/src/applications/search/engine/PhabricatorApplicationSearchEngine.php b/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
--- a/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
+++ b/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
@@ -127,6 +127,10 @@
       }
     }
 
+    if ($object instanceof PhabricatorCustomFieldInterface) {
+      $this->applyCustomFieldsToQuery($query, $saved);
+    }
+
     return $query;
   }
 
@@ -192,6 +196,10 @@
       }
     }
 
+    foreach ($this->buildCustomFieldSearchFields() as $custom_field) {
+      $fields[] = $custom_field;
+    }
+
     return $fields;
   }
 
@@ -1094,14 +1102,22 @@
   }
 
 
-  /**
-   * Add inputs to an application search form so the user can query on custom
-   * fields.
-   *
-   * @param AphrontFormView Form to update.
-   * @param PhabricatorSavedQuery Values to prefill.
-   * @return void
-   */
+  protected function buildCustomFieldSearchFields() {
+    $list = $this->getCustomFieldList();
+    if (!$list) {
+      return array();
+    }
+
+    $fields = array();
+    foreach ($list->getFields() as $field) {
+      $fields[] = id(new PhabricatorSearchCustomFieldProxyField())
+        ->setSearchEngine($this)
+        ->setCustomField($field);
+    }
+    return $fields;
+  }
+
+  // TODO: Remove.
   protected function appendCustomFieldsToForm(
     AphrontFormView $form,
     PhabricatorSavedQuery $saved) {
diff --git a/src/applications/search/field/PhabricatorSearchCustomFieldProxyField.php b/src/applications/search/field/PhabricatorSearchCustomFieldProxyField.php
new file mode 100644
--- /dev/null
+++ b/src/applications/search/field/PhabricatorSearchCustomFieldProxyField.php
@@ -0,0 +1,58 @@
+<?php
+
+final class PhabricatorSearchCustomFieldProxyField
+  extends PhabricatorSearchField {
+
+  private $searchEngine;
+  private $customField;
+
+  public function setSearchEngine(PhabricatorApplicationSearchEngine $engine) {
+    $this->searchEngine = $engine;
+    return $this;
+  }
+
+  public function getSearchEngine() {
+    return $this->searchEngine;
+  }
+
+  public function setCustomField(PhabricatorCustomField $field) {
+    $this->customField = $field;
+    $this->setKey('custom:'.$field->getFieldIndex());
+
+    $aliases = array();
+    $aliases[] = $field->getFieldKey();
+    $this->setAliases($aliases);
+
+    return $this;
+  }
+
+  public function getCustomField() {
+    return $this->customField;
+  }
+
+  protected function getDefaultValue() {
+    return null;
+  }
+
+  protected function getValueExistsInRequest(AphrontRequest $request, $key) {
+    // TODO: For historical reasons, the keys we look for don't line up with
+    // the keys that CustomFields use. Just skip the check for existence and
+    // always read the value. It would be vaguely nice to make rendering more
+    // consistent instead.
+    return true;
+  }
+
+  protected function getValueFromRequest(AphrontRequest $request, $key) {
+    return $this->getCustomField()->readApplicationSearchValueFromRequest(
+      $this->getSearchEngine(),
+      $request);
+  }
+
+  public function appendToForm(AphrontFormView $form) {
+    return $this->getCustomField()->appendToApplicationSearchForm(
+      $this->getSearchEngine(),
+      $form,
+      $this->getValue());
+  }
+
+}
diff --git a/src/applications/search/field/PhabricatorSearchDatasourceField.php b/src/applications/search/field/PhabricatorSearchDatasourceField.php
new file mode 100644
--- /dev/null
+++ b/src/applications/search/field/PhabricatorSearchDatasourceField.php
@@ -0,0 +1,17 @@
+<?php
+
+final class PhabricatorSearchDatasourceField
+  extends PhabricatorSearchTokenizerField {
+
+  private $datasource;
+
+  protected function newDatasource() {
+    return id(clone $this->datasource);
+  }
+
+  public function setDatasource(PhabricatorTypeaheadDatasource $datasource) {
+    $this->datasource = $datasource;
+    return $this;
+  }
+
+}
diff --git a/src/applications/search/field/PhabricatorSearchField.php b/src/applications/search/field/PhabricatorSearchField.php
--- a/src/applications/search/field/PhabricatorSearchField.php
+++ b/src/applications/search/field/PhabricatorSearchField.php
@@ -209,7 +209,9 @@
 /* -(  Rendering Controls  )------------------------------------------------- */
 
 
-  abstract protected function newControl();
+  protected function newControl() {
+    throw new PhutilMethodNotImplementedException();
+  }
 
 
   protected function renderControl() {
diff --git a/src/applications/search/field/PhabricatorSearchOwnersField.php b/src/applications/search/field/PhabricatorSearchOwnersField.php
new file mode 100644
--- /dev/null
+++ b/src/applications/search/field/PhabricatorSearchOwnersField.php
@@ -0,0 +1,18 @@
+<?php
+
+final class PhabricatorSearchOwnersField
+  extends PhabricatorSearchTokenizerField {
+
+  protected function getDefaultValue() {
+    return array();
+  }
+
+  protected function getValueFromRequest(AphrontRequest $request, $key) {
+    return $this->getUsersFromRequest($request, $key);
+  }
+
+  protected function newDatasource() {
+    return new PhabricatorPeopleOwnerDatasource();
+  }
+
+}
diff --git a/src/applications/search/field/PhabricatorSearchSelectField.php b/src/applications/search/field/PhabricatorSearchSelectField.php
new file mode 100644
--- /dev/null
+++ b/src/applications/search/field/PhabricatorSearchSelectField.php
@@ -0,0 +1,30 @@
+<?php
+
+final class PhabricatorSearchSelectField
+  extends PhabricatorSearchField {
+
+  private $options;
+
+  public function setOptions(array $options) {
+    $this->options = $options;
+    return $this;
+  }
+
+  public function getOptions() {
+    return $this->options;
+  }
+
+  protected function getDefaultValue() {
+    return null;
+  }
+
+  protected function getValueFromRequest(AphrontRequest $request, $key) {
+    return $request->getStr($key);
+  }
+
+  protected function newControl() {
+    return id(new AphrontFormSelectControl())
+      ->setOptions($this->getOptions());
+  }
+
+}
diff --git a/src/applications/search/field/PhabricatorSearchTextField.php b/src/applications/search/field/PhabricatorSearchTextField.php
new file mode 100644
--- /dev/null
+++ b/src/applications/search/field/PhabricatorSearchTextField.php
@@ -0,0 +1,18 @@
+<?php
+
+final class PhabricatorSearchTextField
+  extends PhabricatorSearchField {
+
+  protected function getDefaultValue() {
+    return '';
+  }
+
+  protected function getValueFromRequest(AphrontRequest $request, $key) {
+    return $request->getStr($key);
+  }
+
+  protected function newControl() {
+    return new AphrontFormTextControl();
+  }
+
+}
diff --git a/src/applications/search/field/PhabricatorSearchTokenizerField.php b/src/applications/search/field/PhabricatorSearchTokenizerField.php
--- a/src/applications/search/field/PhabricatorSearchTokenizerField.php
+++ b/src/applications/search/field/PhabricatorSearchTokenizerField.php
@@ -25,4 +25,44 @@
 
   abstract protected function newDatasource();
 
+
+  protected function getUsersFromRequest(AphrontRequest $request, $key) {
+    $list = $this->getListFromRequest($request, $key);
+    $allow_types = array();
+
+    $phids = array();
+    $names = array();
+    $allow_types = array_fuse($allow_types);
+    $user_type = PhabricatorPeopleUserPHIDType::TYPECONST;
+    foreach ($list as $item) {
+      $type = phid_get_type($item);
+      if ($type == $user_type) {
+        $phids[] = $item;
+      } else if (isset($allow_types[$type])) {
+        $phids[] = $item;
+      } else {
+        if (PhabricatorTypeaheadDatasource::isFunctionToken($item)) {
+          // If this is a function, pass it through unchanged; we'll evaluate
+          // it later.
+          $phids[] = $item;
+        } else {
+          $names[] = $item;
+        }
+      }
+    }
+
+    if ($names) {
+      $users = id(new PhabricatorPeopleQuery())
+        ->setViewer($this->getViewer())
+        ->withUsernames($names)
+        ->execute();
+      foreach ($users as $user) {
+        $phids[] = $user->getPHID();
+      }
+      $phids = array_unique($phids);
+    }
+
+    return $phids;
+  }
+
 }
diff --git a/src/applications/search/field/PhabricatorSearchUsersField.php b/src/applications/search/field/PhabricatorSearchUsersField.php
--- a/src/applications/search/field/PhabricatorSearchUsersField.php
+++ b/src/applications/search/field/PhabricatorSearchUsersField.php
@@ -7,47 +7,12 @@
     return array();
   }
 
-  protected function newDatasource() {
-    return new PhabricatorPeopleUserFunctionDatasource();
-  }
-
   protected function getValueFromRequest(AphrontRequest $request, $key) {
-    $list = $this->getListFromRequest($request, $key);
-    $allow_types = array();
-
-    $phids = array();
-    $names = array();
-    $allow_types = array_fuse($allow_types);
-    $user_type = PhabricatorPeopleUserPHIDType::TYPECONST;
-    foreach ($list as $item) {
-      $type = phid_get_type($item);
-      if ($type == $user_type) {
-        $phids[] = $item;
-      } else if (isset($allow_types[$type])) {
-        $phids[] = $item;
-      } else {
-        if (PhabricatorTypeaheadDatasource::isFunctionToken($item)) {
-          // If this is a function, pass it through unchanged; we'll evaluate
-          // it later.
-          $phids[] = $item;
-        } else {
-          $names[] = $item;
-        }
-      }
-    }
-
-    if ($names) {
-      $users = id(new PhabricatorPeopleQuery())
-        ->setViewer($this->getViewer())
-        ->withUsernames($names)
-        ->execute();
-      foreach ($users as $user) {
-        $phids[] = $user->getPHID();
-      }
-      $phids = array_unique($phids);
-    }
+    return $this->getUsersFromRequest($request, $key);
+  }
 
-    return $phids;
+  protected function newDatasource() {
+    return new PhabricatorPeopleUserFunctionDatasource();
   }
 
 }