diff --git a/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php b/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php
index 2b34f55..1b22149 100644
--- a/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php
+++ b/src/markup/engine/__tests__/PhutilRemarkupEngineTestCase.php
@@ -1,114 +1,115 @@
 <?php
 
 /**
  * Test cases for @{class:PhutilRemarkupEngine}.
  *
  * @group testcase
  */
 final class PhutilRemarkupEngineTestCase extends PhutilTestCase {
 
   public function testEngine() {
     $root = dirname(__FILE__).'/remarkup/';
     foreach (Filesystem::listDirectory($root, $hidden = false) as $file) {
       $this->markupText($root.$file);
     }
   }
 
   private function markupText($markup_file) {
     $contents = Filesystem::readFile($markup_file);
     $file = basename($markup_file);
 
     $parts = explode("\n~~~~~~~~~~\n", $contents);
     $this->assertEqual(3, count($parts), $markup_file);
 
     list($input_remarkup, $expected_output, $expected_text) = $parts;
 
     $engine = $this->buildNewTestEngine();
 
     switch ($file) {
       case 'raw-escape.txt':
 
         // NOTE: Here, we want to test PhutilRemarkupRuleEscapeRemarkup and
         // PhutilRemarkupBlockStorage, which are triggered by "\1". In the
         // test, "~" is used as a placeholder for "\1" since it's hard to type
         // "\1".
 
         $input_remarkup = str_replace("~", "\1", $input_remarkup);
         $expected_output = str_replace("~", "\1", $expected_output);
         $expected_text = str_replace("~", "\1", $expected_text);
         break;
       case 'toc.txt':
         $engine->setConfig('header.generate-toc', true);
         break;
     }
 
     $actual_output = (string)$engine->markupText($input_remarkup);
 
     switch ($file) {
       case 'toc.txt':
         $table_of_contents =
           PhutilRemarkupEngineRemarkupHeaderBlockRule::renderTableOfContents(
             $engine);
         $actual_output = $table_of_contents."\n\n".$actual_output;
         break;
     }
 
     $this->assertEqual(
       $expected_output,
       $actual_output,
       "Failed to markup HTML in file '{$file}'.");
 
     $engine->setMode(PhutilRemarkupEngine::MODE_TEXT);
     $actual_output = (string)$engine->markupText($input_remarkup);
 
     $this->assertEqual(
       $expected_text,
       $actual_output,
       "Failed to markup text in file '{$file}'.");
   }
 
   private function buildNewTestEngine() {
     $engine = new PhutilRemarkupEngine();
     $engine->setConfig('uri.prefix', 'http://www.example.com/');
 
     $engine->setConfig(
       'uri.allowed-protocols',
       array(
         'http' => true,
+        'mailto' => true,
       ));
 
     $rules = array();
     $rules[] = new PhutilRemarkupRuleEscapeRemarkup();
     $rules[] = new PhutilRemarkupRuleMonospace();
     $rules[] = new PhutilRemarkupRuleDocumentLink();
     $rules[] = new PhutilRemarkupRuleHyperlink();
     $rules[] = new PhutilRemarkupRuleBold();
     $rules[] = new PhutilRemarkupRuleItalic();
     $rules[] = new PhutilRemarkupRuleDel();
     $rules[] = new PhutilRemarkupRuleUnderline();
 
     $blocks = array();
     $blocks[] = new PhutilRemarkupEngineRemarkupQuotesBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupHeaderBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupHorizontalRuleBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupCodeBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupLiteralBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupNoteBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupTableBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupSimpleTableBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupDefaultBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupListBlockRule();
     $blocks[] = new PhutilRemarkupEngineRemarkupInterpreterRule();
 
     foreach ($blocks as $block) {
       if (!($block instanceof PhutilRemarkupEngineRemarkupCodeBlockRule)) {
         $block->setMarkupRules($rules);
       }
     }
 
     $engine->setBlockRules($blocks);
 
     return $engine;
   }
 
 }
diff --git a/src/markup/engine/__tests__/remarkup/link-mailto.txt b/src/markup/engine/__tests__/remarkup/link-mailto.txt
new file mode 100644
index 0000000..95a1eb9
--- /dev/null
+++ b/src/markup/engine/__tests__/remarkup/link-mailto.txt
@@ -0,0 +1,18 @@
+[[ mailto:alincoln@example.com | mail me ]]
+
+[ mail me ]( mailto:alincoln@example.com )
+
+[[mailto:alincoln@example.com]]
+
+~~~~~~~~~~
+<p><a href="mailto:alincoln@example.com" target="_blank" rel="noreferrer">mail me</a></p>
+
+<p><a href="mailto:alincoln@example.com" target="_blank" rel="noreferrer">mail me</a></p>
+
+<p><a href="mailto:alincoln@example.com" target="_blank" rel="noreferrer">alincoln@example.com</a></p>
+~~~~~~~~~~
+mail me <alincoln@example.com>
+
+mail me <alincoln@example.com>
+
+alincoln@example.com
diff --git a/src/markup/engine/remarkup/markuprule/PhutilRemarkupRuleDocumentLink.php b/src/markup/engine/remarkup/markuprule/PhutilRemarkupRuleDocumentLink.php
index 2bb0c4b..ee33577 100644
--- a/src/markup/engine/remarkup/markuprule/PhutilRemarkupRuleDocumentLink.php
+++ b/src/markup/engine/remarkup/markuprule/PhutilRemarkupRuleDocumentLink.php
@@ -1,119 +1,126 @@
 <?php
 
 /**
  * @group markup
  */
 final class PhutilRemarkupRuleDocumentLink
   extends PhutilRemarkupRule {
 
   public function getPriority() {
     return 300.0;
   }
 
   public function apply($text) {
 
     // Handle mediawiki-style links: [[ href | name ]]
     $text = preg_replace_callback(
       '@\B\\[\\[([^|\\]]+)(?:\\|([^\\]]+))?\\]\\]\B@U',
       array($this, 'markupDocumentLink'),
       $text);
 
     // Handle markdown-style links: [name](href)
     $text = preg_replace_callback(
       '@\B\\[([^\\]]+)\\]\\(([^\\)]+)\\)\B@U',
       array($this, 'markupAlternateLink'),
       $text);
 
     return $text;
   }
 
   protected function renderHyperlink($link, $name) {
     if ($this->getEngine()->isTextMode()) {
       $text = $link;
       if (strncmp($link, '/', 1) == 0 || strncmp($link, '#', 1) == 0) {
         $base = $this->getEngine()->getConfig('uri.prefix');
         if (strncmp($link, '/', 1) == 0) {
           $base = rtrim($base, '/');
         }
         $text = $base.$text;
       }
+
+      // If present, strip off "mailto:".
+      $text = preg_replace('/^mailto:/', '', $text);
+
       if ($link == $name) {
         return $text;
       }
       return $name.' <'.$text.'>';
     }
 
     // By default, we open links in a new window or tab. For anchors on the same
     // page, just jump normally.
     $target = '_blank';
     if (strncmp($link, '#', 1) == 0) {
       $target = null;
     }
 
+    $name = preg_replace('/^mailto:/', '', $name);
+
     if ($this->getEngine()->getState('toc')) {
       return $name;
     } else {
       return phutil_tag(
         'a',
         array(
           'href'    => $link,
           'target'  => $target,
         ),
         $name);
     }
   }
 
   public function markupAlternateLink($matches) {
     $uri = trim($matches[2]);
 
     // NOTE: We apply some special rules to avoid false positives here. The
     // major concern is that we do not want to convert `x[0][1](y)` in a
     // discussion about C source code into a link. To this end, we:
     //
     //   - Don't match at word boundaries;
-    //   - require the URI to contain a "/" character; and
+    //   - require the URI to contain a "/" character or "@" character; and
     //   - reject URIs which being with a quote character.
 
     if ($uri[0] == '"' || $uri[0] == "'" || $uri[0] == '`') {
       return $matches[0];
     }
 
-    if (strpos($uri, '/') === false) {
+    if (strpos($uri, '/') === false &&
+        strpos($uri, '@') === false) {
       return $matches[0];
     }
 
     return $this->markupDocumentLink(
       array(
         $matches[0],
         $matches[2],
         $matches[1],
       ));
   }
 
   public function markupDocumentLink($matches) {
     $uri = trim($matches[1]);
     $name = trim(idx($matches, 2, $uri));
 
     // If whatever is being linked to begins with "/" or "#", or has "://",
-    // treat it as a URI instead of a wiki page.
-    $is_uri = preg_match('@(^/)|(://)|(^#)@', $uri);
+    // or is "mailto:", treat it as a URI instead of a wiki page.
+    $is_uri = preg_match('@(^/)|(://)|(^#)|(^mailto:)@', $uri);
 
     if ($is_uri && strncmp('/', $uri, 1) && strncmp('#', $uri, 1)) {
       $protocols = $this->getEngine()->getConfig(
         'uri.allowed-protocols',
         array());
       $protocol = id(new PhutilURI($uri))->getProtocol();
       if (!idx($protocols, $protocol)) {
         // Don't treat this as a URI if it's not an allowed protocol.
         $is_uri = false;
       }
     }
 
     if (!$is_uri) {
       return $matches[0];
     }
 
     return $this->getEngine()->storeText($this->renderHyperlink($uri, $name));
   }
 
 }