diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4f0144b0..8e459314 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,7 +21,7 @@ option (SYNERGY_BUILD_LEGACY_GUI "Build the legacy GUI" ON)
 option (SYNERGY_BUILD_LEGACY_SERVICE "Build the legacy service (synergyd)" ON)
 option (SYNERGY_BUILD_LEGACY_INSTALLER "Build the legacy installer" ON)
 
-if (DEFINED $ENV{SYNERGY_ENTERPRISE})
+if (DEFINED ENV{SYNERGY_ENTERPRISE})
   option (SYNERGY_ENTERPRISE "Build Enterprise" ON)
 else()
   option (SYNERGY_ENTERPRISE "Build Enterprise" OFF)