diff --git a/Cantera/cxx/demos/combustor/combustor.cpp b/Cantera/cxx/demos/combustor/combustor.cpp
index b8a3c0c45..8f6c44ff4 100644
--- a/Cantera/cxx/demos/combustor/combustor.cpp
+++ b/Cantera/cxx/demos/combustor/combustor.cpp
@@ -12,6 +12,9 @@
 #include <cantera/IdealGasMix.h>
 
 using namespace CanteraZeroD;
+using namespace Cantera;
+using namespace Cantera_CXX;
+using namespace std;
 
 void runexample() {