diff --git a/requirements-rootless.txt b/requirements-rootless.txt
index 3269922db..16021d1ef 100644
--- a/requirements-rootless.txt
+++ b/requirements-rootless.txt
@@ -1,3 +1,6 @@
+# *** NOTE ***
+# You MUST keep entries in this file in sync with those in requirements.txt
+
 asn1>=2.2.0,<2.3.0
 certifi>=2018.4.16
 chardet>=3.0.4,<3.1
diff --git a/requirements.txt b/requirements.txt
index 3281b7b28..6d902312d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,6 @@
+# *** NOTE ***
+# You MUST keep entries in this file in sync with those in requirements-rootless.txt
+
 asn1>=2.2.0,<2.3.0
 certifi>=2018.4.16
 chardet>=3.0.4,<3.1