diff --git a/cmake/ProjectVariables.cmake b/cmake/ProjectVariables.cmake
index 01757c3..c3cc4d7 100644
--- a/cmake/ProjectVariables.cmake
+++ b/cmake/ProjectVariables.cmake
@@ -17,6 +17,11 @@
 # * PDO_INSTALL_ROOT
 # * PDO_CONTRACT_VERSION
 
+SET(PDO_CONTRACTS_ROOT ${CMAKE_SOURCE_DIR})
+IF (DEFINED ENV{PDO_CONTRACTS_ROOT})
+  SET(PDO_CONTRACTS_ROOT $ENV{PDO_CONTRACTS_ROOT})
+ENDIF()
+
 IF (NOT DEFINED ENV{PDO_SOURCE_ROOT})
   MESSAGE(FATAL_ERROR "PDO_SOURCE_ROOT not defined")
 ENDIF()
@@ -35,7 +40,7 @@ SET(PDO_JUPYTER_ROOT ${PDO_INSTALL_ROOT}/opt/pdo/notebooks)
 # without any annotated version tags)
 EXECUTE_PROCESS(
   COMMAND ./get_version
-  WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}/bin
+  WORKING_DIRECTORY ${PDO_CONTRACTS_ROOT}/bin
   OUTPUT_VARIABLE PDO_CONTRACT_VERSION
   ERROR_QUIET
   OUTPUT_STRIP_TRAILING_WHITESPACE