diff --git a/uiop/run-program.lisp b/uiop/run-program.lisp
index 2986f447cbd27720f1e33527c53d37c9eaf11220..3309d5bb413a999c0b9125902a8ce83b54c7a7fe 100644
--- a/uiop/run-program.lisp
+++ b/uiop/run-program.lisp
@@ -338,7 +338,10 @@ EXTERNAL-FORMAT for the stream passed to the OUTPUT processor."
                          #+lispworks
                          (if interactive
                              (system:call-system-showing-output
+                              #+os-unix
                               (cons "/usr/bin/env" command) ; lispworks wants a full path.
+                              #-os-unix
+                              command
                               :show-cmd nil
                               :wait wait)
                            (system:run-shell-command