diff --git a/driver_library/python/CMakeLists.txt b/driver_library/python/CMakeLists.txt
index 6554730..a16c612 100644
--- a/driver_library/python/CMakeLists.txt
+++ b/driver_library/python/CMakeLists.txt
@@ -33,7 +33,7 @@
 # local env variables passed down to the python scripts
 # scripts can thus be used standalone
 set(DRIVER_ENV ETHOS_U_DRIVER_INCLUDE="${PROJECT_SOURCE_DIR}/include"
-               ETHOS_U_DRIVER_LIB=${PROJECT_BINARY_DIR}/lib)
+               ETHOS_U_DRIVER_LIB="${PROJECT_BINARY_DIR}")
 
 # common step - generates swig wrappers
 add_custom_command(OUTPUT ${OUT_WRAP}