Index: src/__phutil_library_map__.php
===================================================================
--- src/__phutil_library_map__.php
+++ src/__phutil_library_map__.php
@@ -147,6 +147,7 @@
     'ArcanistTextLinter' => 'lint/linter/ArcanistTextLinter.php',
     'ArcanistTextLinterTestCase' => 'lint/linter/__tests__/ArcanistTextLinterTestCase.php',
     'ArcanistTodoWorkflow' => 'workflow/ArcanistTodoWorkflow.php',
+    'ArcanistTrackWorkflow' => 'workflow/ArcanistTrackWorkflow.php',
     'ArcanistUncommittedChangesException' => 'exception/usage/ArcanistUncommittedChangesException.php',
     'ArcanistUnitConsoleRenderer' => 'unit/renderer/ArcanistUnitConsoleRenderer.php',
     'ArcanistUnitRenderer' => 'unit/renderer/ArcanistUnitRenderer.php',
@@ -295,6 +296,7 @@
     'ArcanistTextLinter' => 'ArcanistLinter',
     'ArcanistTextLinterTestCase' => 'ArcanistArcanistLinterTestCase',
     'ArcanistTodoWorkflow' => 'ArcanistBaseWorkflow',
+    'ArcanistTrackWorkflow' => 'ArcanistBaseWorkflow',
     'ArcanistUncommittedChangesException' => 'ArcanistUsageException',
     'ArcanistUnitConsoleRenderer' => 'ArcanistUnitRenderer',
     'ArcanistUnitWorkflow' => 'ArcanistBaseWorkflow',
Index: src/workflow/ArcanistTrackWorkflow.php
===================================================================
--- /dev/null
+++ src/workflow/ArcanistTrackWorkflow.php
@@ -0,0 +1,115 @@
+<?php
+
+/**
+ * Start time tracking on a task
+ *
+ * @group workflow
+ */
+final class ArcanistTrackWorkflow extends ArcanistBaseWorkflow {
+
+  public function getWorkflowName() {
+    return 'track';
+  }
+
+  public function getCommandSynopses() {
+    return phutil_console_format(<<<EOTEXT
+      **track** [__options__]
+EOTEXT
+      );
+  }
+
+  public function getCommandHelp() {
+    return phutil_console_format(<<<EOTEXT
+Track starting and ending work on Phrequent time tracker.
+EOTEXT
+      );
+  }
+
+  public function requiresConduit() {
+    return true;
+  }
+
+  public function desiresWorkingCopy() {
+    return false;
+  }
+
+  public function requiresAuthentication() {
+    return true;
+  }
+
+
+  public function getArguments() {
+    return array(
+      'task' => array(
+        'param' => 'T1234',
+        'help' => "A maniphest task that you are working on.",
+      ),
+      'start' => array(
+        'help' => "Start tracking.",
+      ),
+      'stop' => array(
+        'help' => "Stop tracking.",
+      )
+    );
+  }
+
+  public function run() {
+    $start_flag = $this->getArgument('start');
+    $stop_flag = $this->getArgument('stop');
+
+    if (!$start_flag && !$stop_flag) {
+      echo "Please specify whether to --start or --stop tracking.\n";
+    }
+
+    $object_exists = false;
+    $object_id = null;
+    $object_name = "";
+    $conduit = $this->getConduit();
+
+    if ($this->getArgument('task')) {
+      $object_exists = true;
+
+      $id = $this->getArgument('task');
+      if (!preg_match("/^T?\d+$/", $id)) {
+        echo "Invalid Task ID: {$id}.\n";
+        return 1;
+      }
+      $id = ltrim($id, 'T');
+
+      $info = $conduit->callMethodSynchronous(
+        'maniphest.info',
+        array(
+          'task_id' => $id
+        ));
+
+      $object_id = $info['phid'];
+      $object_name = "T$id: ".$info['title'];
+    }
+
+    if (!$object_exists) {
+      echo "Please specify an object you are working on,";
+      echo "like '--task T1234' for a task\n";
+      return 1;
+    }
+
+    $method_name = $start_flag ? "phrequent.start" : "phrequent.stop";
+
+    $info = $conduit->callMethodSynchronous(
+      $method_name,
+      array(
+        'object' => $object_id
+      ));
+
+    if ($start_flag) {
+      echo phutil_console_format(
+        "<fg:green>Started</fg> tracking time for <fg:blue>**%s**</fg>\n",
+        $object_name);
+    }
+    else {
+      echo phutil_console_format(
+        "<fg:red>Stopped</fg> tracking time for <fg:blue>**%s**</fg>\n",
+        $object_name);
+    }
+  }
+
+}