diff --git a/setup.py b/setup.py
index 8b157e500..c4ecfe348 100644
--- a/setup.py
+++ b/setup.py
@@ -231,6 +231,7 @@ setup(
     cmdclass=dict(build_ext=CMakeBuild, test=PyTest),
     zip_safe=False,
     tests_require=['pytest==3.8'],
+    install_requires=['cmake'],
     packages=['dlib'],
     keywords=['dlib', 'Computer Vision', 'Machine Learning'],
     classifiers=[