diff --git a/test/py/test_cert.readme b/test/py/test_cert.readme
new file mode 100644
index 0000000..08bbbc9
--- /dev/null
+++ b/test/py/test_cert.readme
@@ -0,0 +1,7 @@
+NOTE:
+The test_cert.pem file in this directory must never be used on production systems.
+
+The key it represents is a self-signed key intended only for use by the unit
+testing framework.  It is a publicly exposed private key.
+
+Do not use test_cert.pem in production environments under any circumstances.