diff --git a/resources/sql/autopatches/20160531.pref.01.xaction.sql b/resources/sql/autopatches/20160531.pref.01.xaction.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20160531.pref.01.xaction.sql
@@ -0,0 +1,19 @@
+CREATE TABLE {$NAMESPACE}_user.user_preferencestransaction (
+  id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+  phid VARBINARY(64) NOT NULL,
+  authorPHID VARBINARY(64) NOT NULL,
+  objectPHID VARBINARY(64) NOT NULL,
+  viewPolicy VARBINARY(64) NOT NULL,
+  editPolicy VARBINARY(64) NOT NULL,
+  commentPHID VARBINARY(64) DEFAULT NULL,
+  commentVersion INT UNSIGNED NOT NULL,
+  transactionType VARCHAR(32) COLLATE {$COLLATE_TEXT} NOT NULL,
+  oldValue LONGTEXT COLLATE {$COLLATE_TEXT} NOT NULL,
+  newValue LONGTEXT COLLATE {$COLLATE_TEXT} NOT NULL,
+  contentSource LONGTEXT COLLATE {$COLLATE_TEXT} NOT NULL,
+  metadata LONGTEXT COLLATE {$COLLATE_TEXT} NOT NULL,
+  dateCreated INT UNSIGNED NOT NULL,
+  dateModified INT UNSIGNED NOT NULL,
+  UNIQUE KEY `key_phid` (`phid`),
+  KEY `key_object` (`objectPHID`)
+) ENGINE=InnoDB, COLLATE {$COLLATE_TEXT};
diff --git a/resources/sql/autopatches/20160531.pref.02.datecreatecol.sql b/resources/sql/autopatches/20160531.pref.02.datecreatecol.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20160531.pref.02.datecreatecol.sql
@@ -0,0 +1,2 @@
+ALTER TABLE {$NAMESPACE}_user.user_preferences
+  ADD dateCreated INT UNSIGNED NOT NULL;
diff --git a/resources/sql/autopatches/20160531.pref.03.datemodcol.sql b/resources/sql/autopatches/20160531.pref.03.datemodcol.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20160531.pref.03.datemodcol.sql
@@ -0,0 +1,2 @@
+ALTER TABLE {$NAMESPACE}_user.user_preferences
+  ADD dateModified INT UNSIGNED NOT NULL;
diff --git a/resources/sql/autopatches/20160531.pref.04.datecreateval.sql b/resources/sql/autopatches/20160531.pref.04.datecreateval.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20160531.pref.04.datecreateval.sql
@@ -0,0 +1,2 @@
+UPDATE {$NAMESPACE}_user.user_preferences
+  SET dateCreated = UNIX_TIMESTAMP() WHERE dateCreated = 0;
diff --git a/resources/sql/autopatches/20160531.pref.05.datemodval.sql b/resources/sql/autopatches/20160531.pref.05.datemodval.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20160531.pref.05.datemodval.sql
@@ -0,0 +1,2 @@
+UPDATE {$NAMESPACE}_user.user_preferences
+  SET dateModified = UNIX_TIMESTAMP() WHERE dateModified = 0;
diff --git a/resources/sql/autopatches/20160531.pref.06.phidcol.sql b/resources/sql/autopatches/20160531.pref.06.phidcol.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20160531.pref.06.phidcol.sql
@@ -0,0 +1,2 @@
+ALTER TABLE {$NAMESPACE}_user.user_preferences
+  ADD phid VARBINARY(64) NOT NULL;
diff --git a/resources/sql/autopatches/20160531.pref.07.phidval.php b/resources/sql/autopatches/20160531.pref.07.phidval.php
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20160531.pref.07.phidval.php
@@ -0,0 +1,17 @@
+<?php
+
+$table = new PhabricatorUserPreferences();
+$conn_w = $table->establishConnection('w');
+
+foreach (new LiskMigrationIterator($table) as $row) {
+  if ($row->getPHID() !== '') {
+    continue;
+  }
+
+  queryfx(
+    $conn_w,
+    'UPDATE %T SET phid = %s WHERE id = %d',
+    $table->getTableName(),
+    $table->generatePHID(),
+    $row->getID());
+}
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
@@ -3592,6 +3592,9 @@
     'PhabricatorUserLogView' => 'applications/people/view/PhabricatorUserLogView.php',
     'PhabricatorUserPHIDResolver' => 'applications/phid/resolver/PhabricatorUserPHIDResolver.php',
     'PhabricatorUserPreferences' => 'applications/settings/storage/PhabricatorUserPreferences.php',
+    'PhabricatorUserPreferencesPHIDType' => 'applications/settings/phid/PhabricatorUserPreferencesPHIDType.php',
+    'PhabricatorUserPreferencesQuery' => 'applications/settings/query/PhabricatorUserPreferencesQuery.php',
+    'PhabricatorUserPreferencesTransaction' => 'applications/settings/storage/PhabricatorUserPreferencesTransaction.php',
     'PhabricatorUserProfile' => 'applications/people/storage/PhabricatorUserProfile.php',
     'PhabricatorUserProfileEditor' => 'applications/people/editor/PhabricatorUserProfileEditor.php',
     'PhabricatorUserRealNameField' => 'applications/people/customfield/PhabricatorUserRealNameField.php',
@@ -8342,7 +8345,15 @@
     ),
     'PhabricatorUserLogView' => 'AphrontView',
     'PhabricatorUserPHIDResolver' => 'PhabricatorPHIDResolver',
-    'PhabricatorUserPreferences' => 'PhabricatorUserDAO',
+    'PhabricatorUserPreferences' => array(
+      'PhabricatorUserDAO',
+      'PhabricatorPolicyInterface',
+      'PhabricatorDestructibleInterface',
+      'PhabricatorApplicationTransactionInterface',
+    ),
+    'PhabricatorUserPreferencesPHIDType' => 'PhabricatorPHIDType',
+    'PhabricatorUserPreferencesQuery' => 'PhabricatorCursorPagedPolicyAwareQuery',
+    'PhabricatorUserPreferencesTransaction' => 'PhabricatorApplicationTransaction',
     'PhabricatorUserProfile' => 'PhabricatorUserDAO',
     'PhabricatorUserProfileEditor' => 'PhabricatorApplicationTransactionEditor',
     'PhabricatorUserRealNameField' => 'PhabricatorUserCustomField',
diff --git a/src/applications/conpherence/editor/ConpherenceEditor.php b/src/applications/conpherence/editor/ConpherenceEditor.php
--- a/src/applications/conpherence/editor/ConpherenceEditor.php
+++ b/src/applications/conpherence/editor/ConpherenceEditor.php
@@ -533,13 +533,20 @@
 
   protected function getMailTo(PhabricatorLiskDAO $object) {
     $to_phids = array();
+
     $participants = $object->getParticipants();
-    if (empty($participants)) {
+    if (!$participants) {
       return $to_phids;
     }
-    $preferences = id(new PhabricatorUserPreferences())
-      ->loadAllWhere('userPHID in (%Ls)', array_keys($participants));
+
+    $participant_phids = mpull($participants, 'getParticipantPHID');
+
+    $preferences = id(new PhabricatorUserPreferencesQuery())
+      ->setViewer(PhabricatorUser::getOmnipotentUser())
+      ->withUserPHIDs($participant_phids)
+      ->execute();
     $preferences = mpull($preferences, null, 'getUserPHID');
+
     foreach ($participants as $phid => $participant) {
       $default = ConpherenceSettings::EMAIL_ALWAYS;
       $preference = idx($preferences, $phid);
@@ -557,6 +564,7 @@
         $to_phids[] = $phid;
       }
     }
+
     return $to_phids;
   }
 
diff --git a/src/applications/feed/PhabricatorFeedStoryPublisher.php b/src/applications/feed/PhabricatorFeedStoryPublisher.php
--- a/src/applications/feed/PhabricatorFeedStoryPublisher.php
+++ b/src/applications/feed/PhabricatorFeedStoryPublisher.php
@@ -207,9 +207,10 @@
 
     $tags = $this->getMailTags();
     if ($tags) {
-      $all_prefs = id(new PhabricatorUserPreferences())->loadAllWhere(
-        'userPHID in (%Ls)',
-        $phids);
+      $all_prefs = id(new PhabricatorUserPreferencesQuery())
+        ->setViewer(PhabricatorUser::getOmnipotentUser())
+        ->withUserPHIDs($phids)
+        ->execute();
       $all_prefs = mpull($all_prefs, null, 'getUserPHID');
     }
 
diff --git a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
--- a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
+++ b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
@@ -940,9 +940,10 @@
       }
     }
 
-    $all_prefs = id(new PhabricatorUserPreferences())->loadAllWhere(
-      'userPHID in (%Ls)',
-      $actor_phids);
+    $all_prefs = id(new PhabricatorUserPreferencesQuery())
+      ->setViewer(PhabricatorUser::getOmnipotentUser())
+      ->withUserPHIDs($actor_phids)
+      ->execute();
     $all_prefs = mpull($all_prefs, null, 'getUserPHID');
 
     $value_email = PhabricatorUserPreferences::MAILTAG_PREFERENCE_EMAIL;
diff --git a/src/applications/people/storage/PhabricatorUser.php b/src/applications/people/storage/PhabricatorUser.php
--- a/src/applications/people/storage/PhabricatorUser.php
+++ b/src/applications/people/storage/PhabricatorUser.php
@@ -494,9 +494,10 @@
 
     $preferences = null;
     if ($this->getPHID()) {
-      $preferences = id(new PhabricatorUserPreferences())->loadOneWhere(
-        'userPHID = %s',
-        $this->getPHID());
+      $preferences = id(new PhabricatorUserPreferencesQuery())
+        ->setViewer($this)
+        ->withUsers(array($this))
+        ->executeOne();
     }
 
     if (!$preferences) {
@@ -1293,11 +1294,12 @@
         $external->delete();
       }
 
-      $prefs = id(new PhabricatorUserPreferences())->loadAllWhere(
-        'userPHID = %s',
-        $this->getPHID());
+      $prefs = id(new PhabricatorUserPreferencesQuery())
+        ->setViewer($engine->getViewer())
+        ->withUsers(array($this))
+        ->execute();
       foreach ($prefs as $pref) {
-        $pref->delete();
+        $engine->destroyObject($pref);
       }
 
       $profiles = id(new PhabricatorUserProfile())->loadAllWhere(
diff --git a/src/applications/settings/phid/PhabricatorUserPreferencesPHIDType.php b/src/applications/settings/phid/PhabricatorUserPreferencesPHIDType.php
new file mode 100644
--- /dev/null
+++ b/src/applications/settings/phid/PhabricatorUserPreferencesPHIDType.php
@@ -0,0 +1,40 @@
+<?php
+
+final class PhabricatorUserPreferencesPHIDType extends PhabricatorPHIDType {
+
+  const TYPECONST = 'PSET';
+
+  public function getTypeName() {
+    return pht('Settings');
+  }
+
+  public function newObject() {
+    return new PhabricatorUserPreferences();
+  }
+
+  public function getPHIDTypeApplicationClass() {
+    return 'PhabricatorSettingsApplication';
+  }
+
+  protected function buildQueryForObjects(
+    PhabricatorObjectQuery $query,
+    array $phids) {
+
+    return id(new PhabricatorUserPreferencesQuery())
+      ->withPHIDs($phids);
+  }
+
+  public function loadHandles(
+    PhabricatorHandleQuery $query,
+    array $handles,
+    array $objects) {
+
+    $viewer = $query->getViewer();
+    foreach ($handles as $phid => $handle) {
+      $preferences = $objects[$phid];
+
+      $handle->setName(pht('Settings %d', $preferences->getID()));
+    }
+  }
+
+}
diff --git a/src/applications/settings/query/PhabricatorUserPreferencesQuery.php b/src/applications/settings/query/PhabricatorUserPreferencesQuery.php
new file mode 100644
--- /dev/null
+++ b/src/applications/settings/query/PhabricatorUserPreferencesQuery.php
@@ -0,0 +1,118 @@
+<?php
+
+final class PhabricatorUserPreferencesQuery
+  extends PhabricatorCursorPagedPolicyAwareQuery {
+
+  private $ids;
+  private $phids;
+  private $userPHIDs;
+  private $users = array();
+
+  public function withIDs(array $ids) {
+    $this->ids = $ids;
+    return $this;
+  }
+
+  public function withPHIDs(array $phids) {
+    $this->phids = $phids;
+    return $this;
+  }
+
+  public function withUserPHIDs(array $phids) {
+    $this->userPHIDs = $phids;
+    return $this;
+  }
+
+  public function withUsers(array $users) {
+    assert_instances_of($users, 'PhabricatorUser');
+    $this->users = mpull($users, null, 'getPHID');
+    $this->withUserPHIDs(array_keys($this->users));
+    return $this;
+  }
+
+  public function newResultObject() {
+    return new PhabricatorUserPreferences();
+  }
+
+  protected function loadPage() {
+    return $this->loadStandardPage($this->newResultObject());
+  }
+
+  protected function willFilterPage(array $prefs) {
+    $user_phids = mpull($prefs, 'getUserPHID');
+    $user_phids = array_filter($user_phids);
+
+    // If some of the preferences are attached to users, try to use any objects
+    // we were handed first. If we're missing some, load them.
+
+    if ($user_phids) {
+      $users = $this->users;
+
+      $user_phids = array_fuse($user_phids);
+      $load_phids = array_diff_key($user_phids, $users);
+      $load_phids = array_keys($load_phids);
+
+      if ($load_phids) {
+        $load_users = id(new PhabricatorPeopleQuery())
+          ->setViewer($this->getViewer())
+          ->withPHIDs($load_phids)
+          ->execute();
+        $load_users = mpull($load_users, null, 'getPHID');
+        $users += $load_users;
+      }
+    } else {
+      $users = array();
+    }
+
+    foreach ($prefs as $key => $pref) {
+      $user_phid = $pref->getUserPHID();
+      if (!$user_phid) {
+        $pref->attachUser(null);
+        continue;
+      }
+
+      $user = idx($users, $user_phid);
+      if (!$user) {
+        $this->didRejectResult($pref);
+        unset($prefs[$key]);
+        continue;
+      }
+
+      $pref->attachUser($user);
+    }
+
+    return $prefs;
+  }
+
+  protected function buildWhereClauseParts(AphrontDatabaseConnection $conn) {
+    $where = parent::buildWhereClauseParts($conn);
+
+    if ($this->ids !== null) {
+      $where[] = qsprintf(
+        $conn,
+        'id IN (%Ld)',
+        $this->ids);
+    }
+
+    if ($this->phids !== null) {
+      $where[] = qsprintf(
+        $conn,
+        'phid IN (%Ls)',
+        $this->phids);
+    }
+
+    if ($this->userPHIDs !== null) {
+      $where[] = qsprintf(
+        $conn,
+        'userPHID IN (%Ls)',
+        $this->userPHIDs);
+    }
+
+    return $where;
+  }
+
+  public function getQueryApplicationClass() {
+    return 'PhabricatorSettingsApplication';
+  }
+
+}
diff --git a/src/applications/settings/storage/PhabricatorUserPreferences.php b/src/applications/settings/storage/PhabricatorUserPreferences.php
--- a/src/applications/settings/storage/PhabricatorUserPreferences.php
+++ b/src/applications/settings/storage/PhabricatorUserPreferences.php
@@ -1,6 +1,11 @@
 <?php
 
-final class PhabricatorUserPreferences extends PhabricatorUserDAO {
+final class PhabricatorUserPreferences
+  extends PhabricatorUserDAO
+  implements
+    PhabricatorPolicyInterface,
+    PhabricatorDestructibleInterface,
+    PhabricatorApplicationTransactionInterface {
 
   const PREFERENCE_MONOSPACED           = 'monospaced';
   const PREFERENCE_DARK_CONSOLE         = 'dark_console';
@@ -51,12 +56,14 @@
   protected $userPHID;
   protected $preferences = array();
 
+  private $user = self::ATTACHABLE;
+
   protected function getConfiguration() {
     return array(
+      self::CONFIG_AUX_PHID => true,
       self::CONFIG_SERIALIZATION => array(
         'preferences' => self::SERIALIZATION_JSON,
       ),
-      self::CONFIG_TIMESTAMPS => false,
       self::CONFIG_KEY_SCHEMA => array(
         'userPHID' => array(
           'columns' => array('userPHID'),
@@ -66,6 +73,11 @@
     ) + parent::getConfiguration();
   }
 
+  public function generatePHID() {
+    return PhabricatorPHID::generateNewPHID(
+      PhabricatorUserPreferencesPHIDType::TYPECONST);
+  }
+
   public function getPreference($key, $default = null) {
     return idx($this->preferences, $key, $default);
   }
@@ -115,4 +127,107 @@
     return preg_replace('([^a-z0-9 ,"./]+)i', '', $monospaced);
   }
 
+  public function attachUser(PhabricatorUser $user = null) {
+    $this->user = $user;
+    return $this;
+  }
+
+  public function getUser() {
+    return $this->assertAttached($this->user);
+  }
+
+  public function hasManagedUser() {
+    $user_phid = $this->getUserPHID();
+    if (!$user_phid) {
+      return false;
+    }
+
+    $user = $this->getUser();
+    if ($user->getIsSystemAgent() || $user->getIsMailingList()) {
+      return true;
+    }
+
+    return false;
+  }
+
+
+/* -(  PhabricatorPolicyInterface  )----------------------------------------- */
+
+
+  public function getCapabilities() {
+    return array(
+      PhabricatorPolicyCapability::CAN_VIEW,
+      PhabricatorPolicyCapability::CAN_EDIT,
+    );
+  }
+
+  public function getPolicy($capability) {
+    switch ($capability) {
+      case PhabricatorPolicyCapability::CAN_VIEW:
+        $user_phid = $this->getUserPHID();
+        if ($user_phid) {
+          return $user_phid;
+        }
+
+        return PhabricatorPolicies::getMostOpenPolicy();
+      case PhabricatorPolicyCapability::CAN_EDIT:
+        if ($this->hasManagedUser()) {
+          return PhabricatorPolicies::POLICY_ADMIN;
+        }
+
+        $user_phid = $this->getUserPHID();
+        if ($user_phid) {
+          return $user_phid;
+        }
+
+        return PhabricatorPolicies::POLICY_ADMIN;
+    }
+  }
+
+  public function hasAutomaticCapability($capability, PhabricatorUser $viewer) {
+    if ($this->hasManagedUser()) {
+      if ($viewer->getIsAdmin()) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  public function describeAutomaticCapability($capability) {
+    return null;
+  }
+
+
+/* -(  PhabricatorDestructibleInterface  )----------------------------------- */
+
+
+  public function destroyObjectPermanently(
+    PhabricatorDestructionEngine $engine) {
+    $this->delete();
+  }
+
+
+/* -(  PhabricatorApplicationTransactionInterface  )------------------------- */
+
+
+  public function getApplicationTransactionEditor() {
+    // TODO: Implement.
+    throw new PhutilMethodNotImplementedException();
+  }
+
+  public function getApplicationTransactionObject() {
+    return $this;
+  }
+
+  public function getApplicationTransactionTemplate() {
+    return new PhabricatorUserPreferencesTransaction();
+  }
+
+  public function willRenderTimeline(
+    PhabricatorApplicationTransactionView $timeline,
+    AphrontRequest $request) {
+    return $timeline;
+  }
+
 }
diff --git a/src/applications/settings/storage/PhabricatorUserPreferencesTransaction.php b/src/applications/settings/storage/PhabricatorUserPreferencesTransaction.php
new file mode 100644
--- /dev/null
+++ b/src/applications/settings/storage/PhabricatorUserPreferencesTransaction.php
@@ -0,0 +1,18 @@
+<?php
+
+final class PhabricatorUserPreferencesTransaction
+  extends PhabricatorApplicationTransaction {
+
+  public function getApplicationName() {
+    return 'user';
+  }
+
+  public function getApplicationTransactionCommentObject() {
+    return null;
+  }
+
+  public function getApplicationTransactionType() {
+    return PhabricatorUserPreferencesPHIDType::TYPECONST;
+  }
+
+}