diff --git a/libs/ardour/system_exec.cc b/libs/ardour/system_exec.cc
index b85b2347ae..aec8956422 100644
--- a/libs/ardour/system_exec.cc
+++ b/libs/ardour/system_exec.cc
@@ -25,7 +25,7 @@
 #include "ardour/filesystem_paths.h"
 #include "ardour/system_exec.h"
 
-using namespace ARDOUR;
+namespace ARDOUR {
 
 char * SystemExec::_vfork_exec_wrapper = NULL;
 
@@ -78,3 +78,5 @@ SystemExec::SystemExec (std::string c, const std::map<char, std::string> subs)
 }
 
 SystemExec::~SystemExec() { }
+
+} // namespace ARDOUR