diff --git a/collects/ffi/com.rkt b/collects/ffi/com.rkt
index fe406af3fe..a2950e58f6 100644
--- a/collects/ffi/com.rkt
+++ b/collects/ffi/com.rkt
@@ -3,6 +3,7 @@
 
 (provide guid? iid? clsid?
          string->guid string->iid string->clsid
+         guid->string
          guid=?
 
          progid->clsid clsid->progid