diff --git a/src/applications/config/check/PhabricatorSetupCheckAPC.php b/src/applications/config/check/PhabricatorSetupCheckAPC.php
index 3eacc03d53..0e72954e01 100644
--- a/src/applications/config/check/PhabricatorSetupCheckAPC.php
+++ b/src/applications/config/check/PhabricatorSetupCheckAPC.php
@@ -6,7 +6,8 @@ final class PhabricatorSetupCheckAPC extends PhabricatorSetupCheck {
     if (!extension_loaded('apc')) {
       $message = pht(
         "Installing the PHP extension 'APC' (Alternative PHP Cache) will ".
-        "dramatically improve performance.");
+        "dramatically improve performance. Note that APC versions 3.1.14 and ".
+        "3.1.15 are broken; 3.1.13 is recommended instead.");
 
       $this
         ->newIssue('extension.apc')
diff --git a/support/PhabricatorStartup.php b/support/PhabricatorStartup.php
index a4d241198d..e4198d163d 100644
--- a/support/PhabricatorStartup.php
+++ b/support/PhabricatorStartup.php
@@ -254,6 +254,21 @@ final class PhabricatorStartup {
         "disable it to run Phabricator. Consult the PHP manual for ".
         "instructions.");
     }
+
+    if (extension_loaded('apc')) {
+      $apc_version = phpversion('apc');
+      $known_bad = array(
+        '3.1.14' => true,
+        '3.1.15' => true,
+      );
+      if (isset($known_bad[$apc_version])) {
+        self::didFatal(
+          "You have APC {$apc_version} installed. This version of APC is ".
+          "known to be bad, and does not work with Phabricator (it will ".
+          "cause Phabricator to fatal unrecoverably with nonsense errors). ".
+          "Downgrade to version 3.1.13.");
+      }
+    }
   }