diff --git a/cibuildwheel/macos.py b/cibuildwheel/macos.py
index 4462c781..c1dfc87c 100644
--- a/cibuildwheel/macos.py
+++ b/cibuildwheel/macos.py
@@ -70,6 +70,7 @@ def build(project_dir, package_name, output_dir, test_command, test_requires, be
         # install pip & wheel
         call([python, get_pip_script, '--no-setuptools', '--no-wheel'], env=env)
         call([pip, '--version'], env=env)
+        call([pip, 'install', '--upgrade', 'setuptools'], env=env)
         call([pip, 'install', 'wheel'], env=env)
         call([pip, 'install', 'delocate'], env=env)
 
diff --git a/cibuildwheel/windows.py b/cibuildwheel/windows.py
index 29e1ebb9..299e160d 100644
--- a/cibuildwheel/windows.py
+++ b/cibuildwheel/windows.py
@@ -74,6 +74,7 @@ def build(project_dir, package_name, output_dir, test_command, test_requires, be
         # prepare the Python environment
         shell(['python', '-m', 'pip', 'install', '--upgrade', 'pip'],
               env=env)
+        shell(['pip', 'install', '--upgrade', 'setuptools'], env=env)
         shell(['pip', 'install', 'wheel'], env=env)
 
         # run the before_build command