diff --git a/test/main.test b/test/main.test
index 322931e..33783fc 100644
--- a/test/main.test
+++ b/test/main.test
@@ -17,6 +17,7 @@ rm a
 # Some VCSes won't show diffs for removed files unless you tell it they are removed:
 [ $VC == 'cvs' ] && cvs rm a
 [ $VC == 'hg'  ] && hg rm a
+[ $VC == 'mtn' ] && mtn drop a
 
 $VC_DIFF > removed.patch || true
 
diff --git a/test/vcs/mtn.sh b/test/vcs/mtn.sh
new file mode 100644
index 0000000..2bd1664
--- /dev/null
+++ b/test/vcs/mtn.sh
@@ -0,0 +1,24 @@
+mtn_init () {
+    WD=$1
+    REPO=$2
+
+    export MTN_KEYDIR=$(mktemp -d "$TESTDIR_ABS/tmp/keydir.XXXXXXX")
+
+    # Monotone doesns't like the db dir to exist when you init it.
+    [ -d "$REPO" ] && rmdir "$REPO"
+
+    mtn --keydir "$MTN_KEYDIR" db init --db="$REPO"
+    mtn --keydir "$MTN_KEYDIR" --db="$REPO" --branch=test setup "$WD"
+    (cd "$WD" && mtn automate generate_key commit-patch-automated-tester@example.com '')
+
+    export VC_DIFF="mtn diff --without-header"
+    export DIFF_PREFIX=""
+}
+
+mtn_cleanup () {
+    WD=$1
+    REPO=$2
+    rm -rf "$REPO"
+    rm -rf "$WD"
+    rm -rf "$MTN_KEYDIR"
+}