diff --git a/src/FontLib/AdobeFontMetrics.php b/src/FontLib/AdobeFontMetrics.php
index 1440c3e..e902e3e 100644
--- a/src/FontLib/AdobeFontMetrics.php
+++ b/src/FontLib/AdobeFontMetrics.php
@@ -33,7 +33,7 @@ function write($file, $encoding = null) {
 
     if ($encoding) {
       $encoding = preg_replace("/[^a-z0-9-_]/", "", $encoding);
-      $map_file = dirname(__FILE__) . "/../maps/$encoding.map";
+      $map_file = dirname(__FILE__) . "/../../maps/$encoding.map";
       if (!file_exists($map_file)) {
         throw new \Exception("Unknown encoding ($encoding)");
       }