diff --git a/resources/celerity/map.php b/resources/celerity/map.php
--- a/resources/celerity/map.php
+++ b/resources/celerity/map.php
@@ -7,7 +7,7 @@
  */
 return array(
   'names' => array(
-    'conpherence.pkg.css' => '3f5d038e',
+    'conpherence.pkg.css' => '9402e1af',
     'conpherence.pkg.js' => '11f3e07e',
     'core.pkg.css' => '55d32e63',
     'core.pkg.js' => '32939240',
@@ -49,7 +49,7 @@
     'rsrc/css/application/conpherence/durable-column.css' => '63114a54',
     'rsrc/css/application/conpherence/header-pane.css' => '517de9fe',
     'rsrc/css/application/conpherence/menu.css' => '78c7b811',
-    'rsrc/css/application/conpherence/message-pane.css' => 'bbbb8a9b',
+    'rsrc/css/application/conpherence/message-pane.css' => '0d7dff02',
     'rsrc/css/application/conpherence/notification.css' => '6cdcc253',
     'rsrc/css/application/conpherence/participant-pane.css' => '7bba0b56',
     'rsrc/css/application/conpherence/transaction.css' => '46253e19',
@@ -621,7 +621,7 @@
     'conpherence-durable-column-view' => '63114a54',
     'conpherence-header-pane-css' => '517de9fe',
     'conpherence-menu-css' => '78c7b811',
-    'conpherence-message-pane-css' => 'bbbb8a9b',
+    'conpherence-message-pane-css' => '0d7dff02',
     'conpherence-notification-css' => '6cdcc253',
     'conpherence-participant-pane-css' => '7bba0b56',
     'conpherence-thread-manager' => '01774ab2',
diff --git a/src/applications/conpherence/ConpherenceTransactionRenderer.php b/src/applications/conpherence/ConpherenceTransactionRenderer.php
--- a/src/applications/conpherence/ConpherenceTransactionRenderer.php
+++ b/src/applications/conpherence/ConpherenceTransactionRenderer.php
@@ -78,6 +78,7 @@
       ->setFullDisplay($full_display);
 
     foreach ($transactions as $transaction) {
+      $collapsed = false;
       if ($previous_transaction) {
         $previous_day = phabricator_format_local_time(
           $previous_transaction->getDateCreated(),
@@ -87,6 +88,22 @@
           $transaction->getDateCreated(),
           $user,
           'Ymd');
+
+        // See if same user / time
+        $previous_author = $previous_transaction->getAuthorPHID();
+        $current_author = $transaction->getAuthorPHID();
+        $previous_time = $previous_transaction->getDateCreated();
+        $current_time = $transaction->getDateCreated();
+        $previous_type = $previous_transaction->getTransactionType();
+        $current_type = $transaction->getTransactionType();
+        if (($previous_author == $current_author) &&
+          ($previous_type == $current_type)) {
+            // Group messages within the last x seconds
+            if (($current_time - $previous_time) < 120) {
+              $collapsed = true;
+            }
+        }
+
         // date marker transaction time!
         if ($previous_day != $current_day) {
           $date_marker_transaction->setDateCreated(
@@ -97,6 +114,9 @@
       }
       $transaction_view = id(clone $transaction_view_template)
         ->setConpherenceTransaction($transaction);
+      if ($collapsed) {
+        $transaction_view->addClass('conpherence-transaction-collapsed');
+      }
 
       $rendered_transactions[] = $transaction_view->render();
       $previous_transaction = $transaction;
diff --git a/webroot/rsrc/css/application/conpherence/message-pane.css b/webroot/rsrc/css/application/conpherence/message-pane.css
--- a/webroot/rsrc/css/application/conpherence/message-pane.css
+++ b/webroot/rsrc/css/application/conpherence/message-pane.css
@@ -390,3 +390,13 @@
   max-height: 200px;
 }
 
+.conpherence-transaction-collapsed .conpherence-transaction-image,
+.conpherence-transaction-collapsed .conpherence-transaction-header {
+  display: none;
+}
+
+.conpherence-message-pane
+  .conpherence-transaction-collapsed.conpherence-transaction-view {
+    margin-top: 0;
+    margin-bottom: 0;
+}