diff --git a/Documentation/config.txt b/Documentation/config.txt
index 3f2fa09a87b..6ea7c76a6af 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -469,6 +469,13 @@ user.name::
 	Can be overridden by the 'GIT_AUTHOR_NAME' and 'GIT_COMMITTER_NAME'
 	environment variables.  See gitlink:git-commit-tree[1].
 
+user.signingkey::
+	If gitlink:git-tag[1] is not selecting the key you want it to
+	automatically when creating a signed tag, you can override the
+	default selection with this variable.  This option is passed
+	unchanged to gpg's --local-user parameter, so you may specify a key
+	using any method that gpg supports.
+
 whatchanged.difftree::
 	The default gitlink:git-diff-tree[1] arguments to be used
 	for gitlink:git-whatchanged[1].
diff --git a/Documentation/git-tag.txt b/Documentation/git-tag.txt
index 13c7aefbf33..3f01e0bfc5e 100644
--- a/Documentation/git-tag.txt
+++ b/Documentation/git-tag.txt
@@ -70,6 +70,16 @@ OPTIONS
 	Take the tag message from the given file.  Use '-' to
 	read the message from the standard input.
 
+CONFIGURATION
+-------------
+By default, git-tag in sign-with-default mode (-s) will use your
+committer identity (of the form "Your Name <your@email.address>") to
+find a key.  If you want to use a different default key, you can specify
+it in the repository configuration as follows:
+
+[user]
+    signingkey = <gpg-key-id>
+
 Author
 ------
 Written by Linus Torvalds <torvalds@osdl.org>,
diff --git a/git-tag.sh b/git-tag.sh
index 94499c9b367..988bf4c6a6b 100755
--- a/git-tag.sh
+++ b/git-tag.sh
@@ -112,7 +112,9 @@ git-check-ref-format "tags/$name" ||
 object=$(git-rev-parse --verify --default HEAD "$@") || exit 1
 type=$(git-cat-file -t $object) || exit 1
 tagger=$(git-var GIT_COMMITTER_IDENT) || exit 1
-: ${username:=$(expr "z$tagger" : 'z\(.*>\)')}
+
+keyid=$(git-repo-config user.signingkey) ||
+	keyid=$(expr "z$tagger" : 'z\(.*>\)')
 
 trap 'rm -f "$GIT_DIR"/TAG_TMP* "$GIT_DIR"/TAG_FINALMSG "$GIT_DIR"/TAG_EDITMSG' 0
 
@@ -139,7 +141,7 @@ if [ "$annotate" ]; then
       cat "$GIT_DIR"/TAG_FINALMSG ) >"$GIT_DIR"/TAG_TMP
     rm -f "$GIT_DIR"/TAG_TMP.asc "$GIT_DIR"/TAG_FINALMSG
     if [ "$signed" ]; then
-	gpg -bsa -u "$username" "$GIT_DIR"/TAG_TMP &&
+	gpg -bsa -u "$keyid" "$GIT_DIR"/TAG_TMP &&
 	cat "$GIT_DIR"/TAG_TMP.asc >>"$GIT_DIR"/TAG_TMP ||
 	die "failed to sign the tag with GPG."
     fi