diff --git a/requirements.txt b/requirements.txt
index 0167debe..47f4bb6c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-numpy>=1.21.1
+numpy>=1.21.1,<2
 pandas>=1.3.1
 scipy>=1.8.1
 SALib>=1.4.4
diff --git a/setup.py b/setup.py
index a0fc80d5..9d8b03dc 100644
--- a/setup.py
+++ b/setup.py
@@ -28,10 +28,10 @@ def get_requirements():
     description='Jupyter notebook support for the MSD ebook',
     long_description=readme(),
     long_description_content_type="text/markdown",
-    python_requires='>=3.6.*, <4',
+    python_requires='>=3.6, <4',
     include_package_data=True,
     install_requires=[
-        "numpy>=1.21.1",
+        "numpy>=1.21.1,<2",
         "scipy>=1.8.1",
         "SALib>=1.4.4",
         "statsmodels>=0.12.2",