diff --git a/src/applications/config/check/PhabricatorExtraConfigSetupCheck.php b/src/applications/config/check/PhabricatorExtraConfigSetupCheck.php
--- a/src/applications/config/check/PhabricatorExtraConfigSetupCheck.php
+++ b/src/applications/config/check/PhabricatorExtraConfigSetupCheck.php
@@ -536,6 +536,9 @@
 
       'differential.whitespace-matters' => pht(
         'Whitespace rendering is now handled automatically.'),
+
+      'phd.pid-directory' => pht(
+        'Phabricator daemons no longer use PID files.'),
     );
 
     return $ancient_config;
diff --git a/src/applications/config/option/PhabricatorPHDConfigOptions.php b/src/applications/config/option/PhabricatorPHDConfigOptions.php
--- a/src/applications/config/option/PhabricatorPHDConfigOptions.php
+++ b/src/applications/config/option/PhabricatorPHDConfigOptions.php
@@ -21,10 +21,6 @@
 
   public function getOptions() {
     return array(
-      $this->newOption('phd.pid-directory', 'string', '/var/tmp/phd/pid')
-        ->setLocked(true)
-        ->setDescription(
-          pht('Directory that phd should use to track running daemons.')),
       $this->newOption('phd.log-directory', 'string', '/var/tmp/phd/log')
         ->setLocked(true)
         ->setDescription(
diff --git a/src/applications/daemon/management/PhabricatorDaemonManagementWorkflow.php b/src/applications/daemon/management/PhabricatorDaemonManagementWorkflow.php
--- a/src/applications/daemon/management/PhabricatorDaemonManagementWorkflow.php
+++ b/src/applications/daemon/management/PhabricatorDaemonManagementWorkflow.php
@@ -12,11 +12,6 @@
       ->selectSymbolsWithoutLoading();
   }
 
-  final protected function getPIDDirectory() {
-    $path = PhabricatorEnv::getEnvConfig('phd.pid-directory');
-    return $this->getControlDirectory($path);
-  }
-
   final protected function getLogDirectory() {
     $path = PhabricatorEnv::getEnvConfig('phd.log-directory');
     return $this->getControlDirectory($path);
@@ -30,11 +25,10 @@
           pht(
             "%s requires the directory '%s' to exist, but it does not exist ".
             "and could not be created. Create this directory or update ".
-            "'%s' / '%s' in your configuration to point to an existing ".
+            "'%s' in your configuration to point to an existing ".
             "directory.",
             'phd',
             $path,
-            'phd.pid-directory',
             'phd.log-directory'));
       }
     }
@@ -146,14 +140,6 @@
       $config['log'] = $this->getLogDirectory().'/daemons.log';
     }
 
-    $pid_dir = $this->getPIDDirectory();
-
-    // TODO: This should be a much better user experience.
-    Filesystem::assertExists($pid_dir);
-    Filesystem::assertIsDirectory($pid_dir);
-    Filesystem::assertWritable($pid_dir);
-
-    $config['piddir'] = $pid_dir;
     $config['daemons'] = $daemons;
 
     $command = csprintf('./phd-daemon %Ls', $flags);
diff --git a/src/infrastructure/daemon/control/PhabricatorDaemonReference.php b/src/infrastructure/daemon/control/PhabricatorDaemonReference.php
--- a/src/infrastructure/daemon/control/PhabricatorDaemonReference.php
+++ b/src/infrastructure/daemon/control/PhabricatorDaemonReference.php
@@ -1,127 +1,9 @@
 <?php
 
-final class PhabricatorDaemonReference extends Phobject {
-
-  private $name;
-  private $argv;
-  private $pid;
-  private $start;
-  private $pidFile;
-
-  private $daemonLog;
-
-  public static function loadReferencesFromFile($path) {
-    $pid_data = Filesystem::readFile($path);
-
-    try {
-      $dict = phutil_json_decode($pid_data);
-    } catch (PhutilJSONParserException $ex) {
-      $dict = array();
-    }
-
-    $refs = array();
-    $daemons = idx($dict, 'daemons', array());
-
-    $logs = array();
-
-    $daemon_ids = ipull($daemons, 'id');
-    if ($daemon_ids) {
-      try {
-        $logs = id(new PhabricatorDaemonLogQuery())
-          ->setViewer(PhabricatorUser::getOmnipotentUser())
-          ->withDaemonIDs($daemon_ids)
-          ->execute();
-      } catch (AphrontQueryException $ex) {
-        // Ignore any issues here; getting this information only allows us
-        // to provide a more complete picture of daemon status, and we want
-        // these commands to work if the database is inaccessible.
-      }
-
-      $logs = mpull($logs, null, 'getDaemonID');
-    }
-
-    // Support PID files that use the old daemon format, where each overseer
-    // had exactly one daemon. We can eventually remove this; they will still
-    // be stopped by `phd stop --force` even if we don't identify them here.
-    if (!$daemons && idx($dict, 'name')) {
-      $daemons = array(
-        array(
-          'config' => array(
-            'class' => idx($dict, 'name'),
-            'argv' => idx($dict, 'argv', array()),
-          ),
-        ),
-      );
-    }
-
-    foreach ($daemons as $daemon) {
-      $ref = new PhabricatorDaemonReference();
-
-      // NOTE: This is the overseer PID, not the actual daemon process PID.
-      // This is correct for checking status and sending signals (the only
-      // things we do with it), but might be confusing. $daemon['pid'] has
-      // the daemon PID, and we could expose that if we had some use for it.
-
-      $ref->pid = idx($dict, 'pid');
-      $ref->start = idx($dict, 'start');
-
-      $config = idx($daemon, 'config', array());
-      $ref->name = idx($config, 'class');
-      $ref->argv = idx($config, 'argv', array());
-
-      $log = idx($logs, idx($daemon, 'id'));
-      if ($log) {
-        $ref->daemonLog = $log;
-      }
-
-      $ref->pidFile = $path;
-      $refs[] = $ref;
-    }
-
-    return $refs;
-  }
+// TODO: See T13321. After the removal of daemon PID files this class
+// no longer makes as much sense as it once did.
 
-  public function updateStatus($new_status) {
-    if (!$this->daemonLog) {
-      return;
-    }
-
-    try {
-      $this->daemonLog
-        ->setStatus($new_status)
-        ->save();
-    } catch (AphrontQueryException $ex) {
-      // Ignore anything that goes wrong here.
-    }
-  }
-
-  public function getPID() {
-    return $this->pid;
-  }
-
-  public function getName() {
-    return $this->name;
-  }
-
-  public function getArgv() {
-    return $this->argv;
-  }
-
-  public function getEpochStarted() {
-    return $this->start;
-  }
-
-  public function getPIDFile() {
-    return $this->pidFile;
-  }
-
-  public function getDaemonLog() {
-    return $this->daemonLog;
-  }
-
-  public function isRunning() {
-    return self::isProcessRunning($this->getPID());
-  }
+final class PhabricatorDaemonReference extends Phobject {
 
   public static function isProcessRunning($pid) {
     if (!$pid) {
@@ -148,15 +30,4 @@
     return $is_running;
   }
 
-  public function waitForExit($seconds) {
-    $start = time();
-    while (time() < $start + $seconds) {
-      usleep(100000);
-      if (!$this->isRunning()) {
-        return true;
-      }
-    }
-    return !$this->isRunning();
-  }
-
 }