diff --git a/avogadro/vtk/CMakeLists.txt b/avogadro/vtk/CMakeLists.txt
index 549626e42f..6cfc703d92 100644
--- a/avogadro/vtk/CMakeLists.txt
+++ b/avogadro/vtk/CMakeLists.txt
@@ -1,3 +1,4 @@
+find_package(OpenGL REQUIRED)
 find_package(GLEW REQUIRED)
 
 if(WIN32 AND NOT BUILD_SHARED_LIBS)