diff --git a/git-flow-hotfix b/git-flow-hotfix
index d3c70ad..efc69a7 100644
--- a/git-flow-hotfix
+++ b/git-flow-hotfix
@@ -19,17 +19,7 @@
 usage() {
 	echo "usage: git flow hotfix [list] [-v]"
 	echo "       git flow hotfix start <version> [<base>]"
-	echo "       git flow hotfix finish <version> [<base>]"
-	# TODO
-	#echo ""
-	#echo "options:"
-	#echo "--option    Explanation"
-	#echo ""
-	#echo "start-only options:"
-	#echo "--option    Explanation"
-	#echo ""
-	#echo "finish-only options:"
-	#echo "--push      Push to the origin repo when finished"
+	echo "       git flow hotfix finish <version>"
 }
 
 cmd_default() {
@@ -98,7 +88,6 @@
 
 	# read arguments into global variables
 	VERSION="$1"
-	BASE="${2:-$MASTER_BRANCH}"
 	BRANCH=$PREFIX$VERSION
 }
 
@@ -110,8 +99,19 @@
 	fi
 }
 
+require_base_is_on_master() {
+	if ! git branch --contains "$BASE" 2>/dev/null \
+			| sed 's/[* ] //g' \
+	  		| grep -q "^$MASTER_BRANCH\$"; then
+		die "fatal: Given base '$BASE' is not a valid commit on '$MASTER_BRANCH'."
+	fi
+}
+
 cmd_start() {
 	parse_args "$@"
+	BASE="${2:-$MASTER_BRANCH}"
+	require_version_arg
+	require_base_is_on_master
 
 	# sanity checks
 	gitflow_require_clean_working_tree
@@ -134,12 +134,13 @@
 	echo "- Start committing your hot fixes"
 	echo "- When done, run:"
 	echo
-	echo "     git flow finish hotfix '$HOTFIX_BRANCH'"
+	echo "     git flow hotfix finish '$VERSION'"
 	echo
 }
 
 cmd_finish() {
 	parse_args "$@"
+	require_version_arg
 
 	# sanity checks
 	gitflow_require_clean_working_tree
@@ -150,17 +151,14 @@
 	gitflow_require_branches_equal $MASTER_BRANCH $ORIGIN/$MASTER_BRANCH
 	gitflow_require_branches_equal $DEVELOP_BRANCH $ORIGIN/$DEVELOP_BRANCH
 
-	# merge into BASE
-	git checkout $BASE
+	# merge into master
+	git checkout $MASTER_BRANCH
 	git merge --no-ff $BRANCH
 	git tag $VERSION_PREFIX$VERSION
 
 	# merge into develop if we fixed a master issue
-	# TODO: merge into support branch
-	if [ "$BASE" = "$MASTER_BRANCH" ]; then
-		git checkout $DEVELOP_BRANCH
-		git merge --no-ff $BRANCH
-	fi
+	git checkout $DEVELOP_BRANCH
+	git merge --no-ff $BRANCH
 
 	# delete branch
 	git branch -d $BRANCH
@@ -171,11 +169,9 @@
 	echo
 	echo "Summary of actions:"
 	echo "- Latest objects have been fetched from '$ORIGIN'"
-	echo "- Hotfix branch has been merged into '$BASE'"
+	echo "- Hotfix branch has been merged into '$MASTER_BRANCH'"
 	echo "- The hotfix was tagged '$VERSION_PREFIX$VERSION'"
-	if [ "$BASE" = "$MASTER_BRANCH" ]; then
-		echo "- Hotfix branch has been back-merged into '$DEVELOP_BRANCH'"
-	fi
+	echo "- Hotfix branch has been back-merged into '$DEVELOP_BRANCH'"
 	echo "- Hotfix branch '$BRANCH' has been deleted"
 	echo
 }