diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt
index 7a2201b0518b2752bcce880e12dd732ed32990d2..8e2c0662ddd72c1bc0765aadbbafd22b62b5adf6 100644
--- a/Documentation/git-checkout.txt
+++ b/Documentation/git-checkout.txt
@@ -419,6 +419,18 @@ $ git reflog -2 HEAD # or
 $ git log -g -2 HEAD
 ------------
 
+ARGUMENT DISAMBIGUATION
+-----------------------
+
+When there is only one argument given and it is not `--` (e.g. "git
+checkout abc"), and when the argument is both a valid `<tree-ish>`
+(e.g. a branch "abc" exists) and a valid `<pathspec>` (e.g. a file
+or a directory whose name is "abc" exists), Git would usually ask
+you to disambiguate.  Because checking out a branch is so common an
+operation, however, "git checkout abc" takes "abc" as a `<tree-ish>`
+in such a situation.  Use `git checkout -- <pathspec>` if you want
+to checkout these paths out of the index.
+
 EXAMPLES
 --------