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
@@ -30,6 +30,7 @@
     'ArcanistCheckstyleXMLLintRenderer' => 'lint/renderer/ArcanistCheckstyleXMLLintRenderer.php',
     'ArcanistChmodLinter' => 'lint/linter/ArcanistChmodLinter.php',
     'ArcanistChmodLinterTestCase' => 'lint/linter/__tests__/ArcanistChmodLinterTestCase.php',
+    'ArcanistClaimWorkflow' => 'workflow/ArcanistClaimWorkflow.php',
     'ArcanistCloseRevisionWorkflow' => 'workflow/ArcanistCloseRevisionWorkflow.php',
     'ArcanistCloseWorkflow' => 'workflow/ArcanistCloseWorkflow.php',
     'ArcanistClosureLinter' => 'lint/linter/ArcanistClosureLinter.php',
@@ -230,6 +231,7 @@
     'ArcanistCheckstyleXMLLintRenderer' => 'ArcanistLintRenderer',
     'ArcanistChmodLinter' => 'ArcanistLinter',
     'ArcanistChmodLinterTestCase' => 'ArcanistLinterTestCase',
+    'ArcanistClaimWorkflow' => 'ArcanistWorkflow',
     'ArcanistCloseRevisionWorkflow' => 'ArcanistWorkflow',
     'ArcanistCloseWorkflow' => 'ArcanistWorkflow',
     'ArcanistClosureLinter' => 'ArcanistExternalLinter',
diff --git a/src/workflow/ArcanistClaimWorkflow.php b/src/workflow/ArcanistClaimWorkflow.php
new file mode 100644
--- /dev/null
+++ b/src/workflow/ArcanistClaimWorkflow.php
@@ -0,0 +1,118 @@
+<?php
+
+/**
+ * Claim a task.
+ */
+final class ArcanistClaimWorkflow extends ArcanistWorkflow {
+
+  public function getWorkflowName() {
+    return 'claim';
+  }
+
+  public function getCommandSynopses() {
+    return phutil_console_format(<<<EOTEXT
+      **claim** __task_id__ [__options__]
+EOTEXT
+      );
+  }
+
+  public function getCommandHelp() {
+    return phutil_console_format(<<<EOTEXT
+        Claim a task for yourself
+EOTEXT
+      );
+  }
+
+  public function requiresConduit() {
+    return true;
+  }
+
+  public function requiresRepositoryAPI() {
+    return false;
+  }
+
+  public function requiresAuthentication() {
+    return true;
+  }
+
+
+  public function getArguments() {
+    return array(
+      '*' => 'task_id',
+      /* 'release' => array(
+        'help' => 'Place the task back up for grabs'
+      )*/
+    );
+  }
+
+  public function run() {
+    $ids = $this->getArgument('task_id');
+    $release = $this->getArgument('release');
+
+    foreach ($ids as $id) {
+      if (!preg_match('/^T?\d+$/', $id)) {
+        echo "Invalid Task ID: {$id}.\n";
+        return 1;
+      }
+      $id = ltrim($id, 'T');
+
+      if ($release) {
+        $result = $this->releaseTask($id);
+
+        if ($result) {
+          echo "T{$id} is up for grabs.\n";
+        } else {
+          echo "T{$id} is not assigned to you.\n";
+        }
+      } else {
+        $result = $this->claimTask($id);
+
+        if ($result) {
+          echo "T{$id} is now assigned to you.\n";
+        } else {
+          echo "T{$id} is already assigned to you.\n";
+        }
+      }
+
+    }
+    return 0;
+  }
+
+  // FIXME: maniphest.update does not accept a single null value
+  private function releaseTask($task_id) {
+    $conduit = $this->getConduit();
+    $info = $conduit->callMethodSynchronous(
+      'maniphest.info',
+      array(
+        'task_id' => $task_id,
+      ));
+    if ($info['ownerPHID'] != $this->getUserPHID()) {
+      return false;
+    }
+    return $conduit->callMethodSynchronous(
+      'maniphest.update',
+      array(
+        'id' => $task_id,
+        'ownerPHID' => null,
+      ));
+  }
+
+  private function claimTask($task_id) {
+    $conduit = $this->getConduit();
+    $info = $conduit->callMethodSynchronous(
+      'maniphest.info',
+      array(
+        'task_id' => $task_id,
+      ));
+    if ($info['ownerPHID'] == $this->getUserPHID()) {
+      return false;
+    }
+    return $conduit->callMethodSynchronous(
+      'maniphest.update',
+      array(
+        'id' => $task_id,
+        'ownerPHID' => $this->getUserPHID(),
+      ));
+  }
+
+}
diff --git a/src/workflow/ArcanistFeatureWorkflow.php b/src/workflow/ArcanistFeatureWorkflow.php
--- a/src/workflow/ArcanistFeatureWorkflow.php
+++ b/src/workflow/ArcanistFeatureWorkflow.php
@@ -31,7 +31,8 @@
 
           With __name__, it creates or checks out a branch. If the branch
           __name__ doesn't exist and is in format D123 then the branch of
-          revision D123 is checked out. Use __start__ to specify where the new
+          revision D123 is checked out. If the format is T123 the corresponding
+          task will be assigned to you. Use __start__ to specify where the new
           branch will start. Use 'arc.feature.start.default' to set the default
           feature start location.
 EOTEXT
@@ -47,7 +48,12 @@
   }
 
   public function requiresAuthentication() {
-    return !$this->getArgument('branch');
+    // We need authentication if the branch specifies a revision or a task
+    $branch = $this->getArgument('branch');
+    if (!isset($branch[0]) || preg_match('/^[DT](\d+)$/', $branch[0])) {
+      return true;
+    }
+    return false;
   }
 
   public function getArguments() {
@@ -140,6 +146,41 @@
               $name);
           }
         } catch (ConduitClientException $ex) {}
+      } else if (preg_match('/^T(\d+)$/', $name, $match)) {
+        // The specified branch looks like a task - Try to assign it to me
+        try {
+          $info = $this->getConduit()->callMethodSynchronous(
+            'maniphest.info',
+            array(
+              'task_id' => $match[1],
+            ));
+
+          if ($info['ownerPHID'] != $this->getUserPHID()) {
+            if ($info['ownerPHID'] != null) {
+              $owner = $this->getConduit()->callMethodSynchronous(
+                'user.query',
+                array(
+                  'phids' => array($info['ownerPHID']),
+                ));
+
+              if (isset($owner[0])) {
+                echo "Task is already assigned to ".$owner[0]['userName'].".\n";
+              } else {
+                echo "Task is already assigned to someone else.\n";
+              }
+            } else {
+              $result = $this->getConduit()->callMethodSynchronous(
+                'maniphest.update',
+                array(
+                  'id' => $match[1],
+                  'ownerPHID' => $this->getUserPHID(),
+                ));
+              if ($result) {
+                echo "T{$match[1]} is now assigned to you.\n";
+              }
+            }
+          }
+        } catch (ConduitClientException $ex) {}
       }
     }