diff --git a/InnerDetector/InDetDetDescr/TRT_ReadoutGeometry/CMakeLists.txt b/InnerDetector/InDetDetDescr/TRT_ReadoutGeometry/CMakeLists.txt
index 17b92b402c590c8a8d32ce3c804c7167ddf9a06c..a576777fc8c6a9632599e103f9b503c03c0e416a 100644
--- a/InnerDetector/InDetDetDescr/TRT_ReadoutGeometry/CMakeLists.txt
+++ b/InnerDetector/InDetDetDescr/TRT_ReadoutGeometry/CMakeLists.txt
@@ -5,6 +5,7 @@ atlas_subdir( TRT_ReadoutGeometry )
 
 # External dependencies:
 find_package( CLHEP )
+find_package( GeoModelCore )
 
 # Component(s) in the package:
 atlas_add_library( TRT_ReadoutGeometry