diff --git a/resources/sql/autopatches/20150724.countdown.comments.1.sql b/resources/sql/autopatches/20150724.countdown.comments.1.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20150724.countdown.comments.1.sql
@@ -0,0 +1,18 @@
+CREATE TABLE {$NAMESPACE}_countdown.countdown_transaction_comment (
+  id INT UNSIGNED NOT NULL PRIMARY KEY AUTO_INCREMENT,
+  phid VARCHAR(64) NOT NULL,
+  transactionPHID VARCHAR(64),
+  authorPHID VARCHAR(64) NOT NULL,
+  viewPolicy VARCHAR(64) NOT NULL,
+  editPolicy VARCHAR(64) NOT NULL,
+  commentVersion INT UNSIGNED NOT NULL,
+  content LONGTEXT NOT NULL COLLATE {$COLLATE_TEXT},
+  contentSource LONGTEXT NOT NULL COLLATE {$COLLATE_TEXT},
+  isDeleted BOOL NOT NULL,
+  dateCreated INT UNSIGNED NOT NULL,
+  dateModified INT UNSIGNED NOT NULL,
+
+  UNIQUE KEY `key_phid` (phid),
+  UNIQUE KEY `key_version` (transactionPHID, commentVersion)
+
+) ENGINE=InnoDB, COLLATE {$COLLATE_TEXT};
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
@@ -1820,6 +1820,7 @@
     'PhabricatorCoreConfigOptions' => 'applications/config/option/PhabricatorCoreConfigOptions.php',
     'PhabricatorCountdown' => 'applications/countdown/storage/PhabricatorCountdown.php',
     'PhabricatorCountdownApplication' => 'applications/countdown/application/PhabricatorCountdownApplication.php',
+    'PhabricatorCountdownCommentController' => 'applications/countdown/controller/PhabricatorCountdownCommentController.php',
     'PhabricatorCountdownController' => 'applications/countdown/controller/PhabricatorCountdownController.php',
     'PhabricatorCountdownCountdownPHIDType' => 'applications/countdown/phid/PhabricatorCountdownCountdownPHIDType.php',
     'PhabricatorCountdownDAO' => 'applications/countdown/storage/PhabricatorCountdownDAO.php',
@@ -1835,6 +1836,7 @@
     'PhabricatorCountdownSchemaSpec' => 'applications/countdown/storage/PhabricatorCountdownSchemaSpec.php',
     'PhabricatorCountdownSearchEngine' => 'applications/countdown/query/PhabricatorCountdownSearchEngine.php',
     'PhabricatorCountdownTransaction' => 'applications/countdown/storage/PhabricatorCountdownTransaction.php',
+    'PhabricatorCountdownTransactionComment' => 'applications/countdown/storage/PhabricatorCountdownTransactionComment.php',
     'PhabricatorCountdownTransactionQuery' => 'applications/countdown/query/PhabricatorCountdownTransactionQuery.php',
     'PhabricatorCountdownView' => 'applications/countdown/view/PhabricatorCountdownView.php',
     'PhabricatorCountdownViewController' => 'applications/countdown/controller/PhabricatorCountdownViewController.php',
@@ -5632,6 +5634,7 @@
       'PhabricatorProjectInterface',
     ),
     'PhabricatorCountdownApplication' => 'PhabricatorApplication',
+    'PhabricatorCountdownCommentController' => 'PhabricatorCountdownController',
     'PhabricatorCountdownController' => 'PhabricatorController',
     'PhabricatorCountdownCountdownPHIDType' => 'PhabricatorPHIDType',
     'PhabricatorCountdownDAO' => 'PhabricatorLiskDAO',
@@ -5647,6 +5650,7 @@
     'PhabricatorCountdownSchemaSpec' => 'PhabricatorConfigSchemaSpec',
     'PhabricatorCountdownSearchEngine' => 'PhabricatorApplicationSearchEngine',
     'PhabricatorCountdownTransaction' => 'PhabricatorApplicationTransaction',
+    'PhabricatorCountdownTransactionComment' => 'PhabricatorApplicationTransactionComment',
     'PhabricatorCountdownTransactionQuery' => 'PhabricatorApplicationTransactionQuery',
     'PhabricatorCountdownView' => 'AphrontTagView',
     'PhabricatorCountdownViewController' => 'PhabricatorCountdownController',
diff --git a/src/applications/countdown/application/PhabricatorCountdownApplication.php b/src/applications/countdown/application/PhabricatorCountdownApplication.php
--- a/src/applications/countdown/application/PhabricatorCountdownApplication.php
+++ b/src/applications/countdown/application/PhabricatorCountdownApplication.php
@@ -42,9 +42,14 @@
       '/countdown/' => array(
         '(?:query/(?P<queryKey>[^/]+)/)?'
           => 'PhabricatorCountdownListController',
-        '(?P<id>[1-9]\d*)/' => 'PhabricatorCountdownViewController',
-        'edit/(?:(?P<id>[1-9]\d*)/)?' => 'PhabricatorCountdownEditController',
-        'delete/(?P<id>[1-9]\d*)/' => 'PhabricatorCountdownDeleteController',
+        '(?P<id>[1-9]\d*)/'
+          => 'PhabricatorCountdownViewController',
+        'comment/(?P<id>[1-9]\d*)/'
+          => 'PhabricatorCountdownCommentController',
+        'edit/(?:(?P<id>[1-9]\d*)/)?'
+          => 'PhabricatorCountdownEditController',
+        'delete/(?P<id>[1-9]\d*)/'
+          => 'PhabricatorCountdownDeleteController',
       ),
     );
   }
diff --git a/src/applications/countdown/controller/PhabricatorCountdownCommentController.php b/src/applications/countdown/controller/PhabricatorCountdownCommentController.php
new file mode 100644
--- /dev/null
+++ b/src/applications/countdown/controller/PhabricatorCountdownCommentController.php
@@ -0,0 +1,63 @@
+<?php
+
+final class PhabricatorCountdownCommentController
+  extends PhabricatorCountdownController {
+
+  public function handleRequest(AphrontRequest $request) {
+    $viewer = $request->getViewer();
+    $id = $request->getURIData('id');
+
+    if (!$request->isFormPost()) {
+      return new Aphront400Response();
+    }
+
+    $countdown = id(new PhabricatorCountdownQuery())
+      ->setViewer($viewer)
+      ->withIDs(array($id))
+      ->executeOne();
+    if (!$countdown) {
+      return new Aphront404Response();
+    }
+
+    $is_preview = $request->isPreviewRequest();
+    $draft = PhabricatorDraft::buildFromRequest($request);
+
+    $view_uri = '/'.$countdown->getMonogram();
+
+    $xactions = array();
+    $xactions[] = id(new PhabricatorCountdownTransaction())
+      ->setTransactionType(PhabricatorTransactions::TYPE_COMMENT)
+      ->attachComment(
+        id(new PhabricatorCountdownTransactionComment())
+          ->setContent($request->getStr('comment')));
+
+    $editor = id(new PhabricatorCountdownEditor())
+      ->setActor($viewer)
+      ->setContinueOnNoEffect($request->isContinueRequest())
+      ->setContentSourceFromRequest($request)
+      ->setIsPreview($is_preview);
+
+    try {
+      $xactions = $editor->applyTransactions($countdown, $xactions);
+    } catch (PhabricatorApplicationTransactionNoEffectException $ex) {
+      return id(new PhabricatorApplicationTransactionNoEffectResponse())
+        ->setCancelURI($view_uri)
+        ->setException($ex);
+    }
+
+    if ($draft) {
+      $draft->replaceOrDelete();
+    }
+
+    if ($request->isAjax() && $is_preview) {
+      return id(new PhabricatorApplicationTransactionResponse())
+        ->setViewer($viewer)
+        ->setTransactions($xactions)
+        ->setIsPreview($is_preview);
+    } else {
+      return id(new AphrontRedirectResponse())
+        ->setURI($view_uri);
+    }
+  }
+
+}
diff --git a/src/applications/countdown/controller/PhabricatorCountdownViewController.php b/src/applications/countdown/controller/PhabricatorCountdownViewController.php
--- a/src/applications/countdown/controller/PhabricatorCountdownViewController.php
+++ b/src/applications/countdown/controller/PhabricatorCountdownViewController.php
@@ -58,19 +58,22 @@
     $timeline = $this->buildTransactionTimeline(
       $countdown,
       new PhabricatorCountdownTransactionQuery());
-    $timeline->setShouldTerminate(true);
+
+    $add_comment = $this->buildCommentForm($countdown);
 
     $content = array(
       $crumbs,
       $object_box,
       $countdown_view,
       $timeline,
+      $add_comment,
     );
 
     return $this->buildApplicationPage(
       $content,
       array(
         'title' => $title,
+        'pageObjects' => array($countdown->getPHID()),
       ));
   }
 
@@ -141,4 +144,25 @@
     return $view;
   }
 
+  private function buildCommentForm(PhabricatorCountdown $countdown) {
+    $viewer = $this->getViewer();
+
+    $is_serious = PhabricatorEnv::getEnvConfig('phabricator.serious-business');
+
+    $add_comment_header = $is_serious
+      ? pht('Add Comment')
+      : pht('Last Words');
+
+    $draft = PhabricatorDraft::newFromUserAndKey(
+      $viewer, $countdown->getPHID());
+
+    return id(new PhabricatorApplicationTransactionCommentView())
+      ->setUser($viewer)
+      ->setObjectPHID($countdown->getPHID())
+      ->setDraft($draft)
+      ->setHeaderText($add_comment_header)
+      ->setAction($this->getApplicationURI('/comment/'.$countdown->getID().'/'))
+      ->setSubmitButtonName(pht('Add Comment'));
+  }
+
 }
diff --git a/src/applications/countdown/editor/PhabricatorCountdownEditor.php b/src/applications/countdown/editor/PhabricatorCountdownEditor.php
--- a/src/applications/countdown/editor/PhabricatorCountdownEditor.php
+++ b/src/applications/countdown/editor/PhabricatorCountdownEditor.php
@@ -22,6 +22,7 @@
     $types[] = PhabricatorTransactions::TYPE_SPACE;
     $types[] = PhabricatorTransactions::TYPE_VIEW_POLICY;
     $types[] = PhabricatorTransactions::TYPE_EDIT_POLICY;
+    $types[] = PhabricatorTransactions::TYPE_COMMENT;
 
     return $types;
   }
diff --git a/src/applications/countdown/storage/PhabricatorCountdownTransaction.php b/src/applications/countdown/storage/PhabricatorCountdownTransaction.php
--- a/src/applications/countdown/storage/PhabricatorCountdownTransaction.php
+++ b/src/applications/countdown/storage/PhabricatorCountdownTransaction.php
@@ -21,7 +21,7 @@
   }
 
   public function getApplicationTransactionCommentObject() {
-    return null;
+    return new PhabricatorCountdownTransactionComment();
   }
 
   public function getTitle() {
diff --git a/src/applications/countdown/storage/PhabricatorCountdownTransactionComment.php b/src/applications/countdown/storage/PhabricatorCountdownTransactionComment.php
new file mode 100644
--- /dev/null
+++ b/src/applications/countdown/storage/PhabricatorCountdownTransactionComment.php
@@ -0,0 +1,10 @@
+<?php
+
+final class PhabricatorCountdownTransactionComment
+  extends PhabricatorApplicationTransactionComment {
+
+  public function getApplicationTransactionObject() {
+    return new PhabricatorCountdownTransaction();
+  }
+
+}