--- config.def.h
+++ config.def.h
@@ -26,9 +26,11 @@ static const Rule rules[] = {
 	 *	WM_CLASS(STRING) = instance, class
 	 *	WM_NAME(STRING) = title
 	 */
-	/* class      instance    title       tags mask     isfloating   monitor */
+	/* class      instance    title       tags mask     isfloating   monitor  isgame */
 	{ "Gimp",     NULL,       NULL,       0,            1,           -1 },
 	{ "Firefox",  NULL,       NULL,       1 << 8,       0,           -1 },
+	{ "Steam",    NULL,       NULL,       0,            0,           -1,      1 },
+	{ "steam_app",NULL,       NULL,       0,            0,           -1,      1 },
 };
 
 /* layout(s) */