diff --git a/README.md b/README.md
index 3c5841c..bc4a4d1 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,9 @@
 ## @digidem/types
 
 Typescript type definitions for untyped modules, for internal use prior to
-publishing on DefinitelyTyped
+publishing on DefinitelyTyped.
+
+_Note: Usage of this module requires Typescript >= 5.1_
 
 ## Usage