diff --git a/src/applications/metamta/controller/PhabricatorMetaMTAMailViewController.php b/src/applications/metamta/controller/PhabricatorMetaMTAMailViewController.php
--- a/src/applications/metamta/controller/PhabricatorMetaMTAMailViewController.php
+++ b/src/applications/metamta/controller/PhabricatorMetaMTAMailViewController.php
@@ -151,6 +151,12 @@
 
     $properties->addTextContent($body);
 
+    $file_phids = $mail->getAttachmentFilePHIDs();
+    if ($file_phids) {
+      $properties->addProperty(
+        pht('Attached Files'),
+        $viewer->loadHandles($file_phids)->renderList());
+    }
 
     return $properties;
   }
diff --git a/src/applications/metamta/storage/PhabricatorMetaMTAAttachment.php b/src/applications/metamta/storage/PhabricatorMetaMTAAttachment.php
--- a/src/applications/metamta/storage/PhabricatorMetaMTAAttachment.php
+++ b/src/applications/metamta/storage/PhabricatorMetaMTAAttachment.php
@@ -1,9 +1,12 @@
 <?php
 
 final class PhabricatorMetaMTAAttachment extends Phobject {
-  protected $data;
-  protected $filename;
-  protected $mimetype;
+
+  private $data;
+  private $filename;
+  private $mimetype;
+  private $file;
+  private $filePHID;
 
   public function __construct($data, $filename, $mimetype) {
     $this->setData($data);
@@ -39,18 +42,49 @@
   }
 
   public function toDictionary() {
+    if (!$this->file) {
+      $iterator = new ArrayIterator(array($this->getData()));
+
+      $source = id(new PhabricatorIteratorFileUploadSource())
+        ->setName($this->getFilename())
+        ->setViewPolicy(PhabricatorPolicies::POLICY_NOONE)
+        ->setMIMEType($this->getMimeType())
+        ->setIterator($iterator);
+
+      $this->file = $source->uploadFile();
+    }
+
     return array(
       'filename' => $this->getFilename(),
       'mimetype' => $this->getMimeType(),
-      'data' => $this->getData(),
+      'filePHID' => $this->file->getPHID(),
     );
   }
 
   public static function newFromDictionary(array $dict) {
-    return new PhabricatorMetaMTAAttachment(
+    $file = null;
+
+    $file_phid = idx($dict, 'filePHID');
+    if ($file_phid) {
+      $file = id(new PhabricatorFileQuery())
+        ->setViewer(PhabricatorUser::getOmnipotentUser())
+        ->withPHIDs(array($file_phid))
+        ->executeOne();
+      if ($file) {
+        $dict['data'] = $file->loadFileData();
+      }
+    }
+
+    $attachment = new self(
       idx($dict, 'data'),
       idx($dict, 'filename'),
       idx($dict, 'mimetype'));
+
+    if ($file) {
+      $attachment->file = $file;
+    }
+
+    return $attachment;
   }
 
 }
diff --git a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
--- a/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
+++ b/src/applications/metamta/storage/PhabricatorMetaMTAMail.php
@@ -197,6 +197,35 @@
     return $result;
   }
 
+  public function getAttachmentFilePHIDs() {
+    $file_phids = array();
+
+    $dictionaries = $this->getParam('attachments');
+    if ($dictionaries) {
+      foreach ($dictionaries as $dictionary) {
+        $file_phid = idx($dictionary, 'filePHID');
+        if ($file_phid) {
+          $file_phids[] = $file_phid;
+        }
+      }
+    }
+
+    return $file_phids;
+  }
+
+  public function loadAttachedFiles(PhabricatorUser $viewer) {
+    $file_phids = $this->getAttachmentFilePHIDs();
+
+    if (!$file_phids) {
+      return array();
+    }
+
+    return id(new PhabricatorFileQuery())
+      ->setViewer($viewer)
+      ->withPHIDs($file_phids)
+      ->execute();
+  }
+
   public function setAttachments(array $attachments) {
     assert_instances_of($attachments, 'PhabricatorMetaMTAAttachment');
     $this->setParam('attachments', mpull($attachments, 'toDictionary'));
@@ -526,6 +555,12 @@
               mpull($cc_actors, 'getEmailAddress'));
             break;
           case 'attachments':
+            $attached_viewer = PhabricatorUser::getOmnipotentUser();
+            $files = $this->loadAttachedFiles($attached_viewer);
+            foreach ($files as $file) {
+              $file->attachToObject($this->getPHID());
+            }
+
             // If the mail content must be encrypted, don't add attachments.
             if ($must_encrypt) {
               break;
@@ -1299,6 +1334,12 @@
 
   public function destroyObjectPermanently(
     PhabricatorDestructionEngine $engine) {
+
+    $files = $this->loadAttachedFiles($engine->getViewer());
+    foreach ($files as $file) {
+      $engine->destroyObject($file);
+    }
+
     $this->delete();
   }