diff --git a/git-force b/git-force
index ce495d1..a7af5a6 100755
--- a/git-force
+++ b/git-force
@@ -7,6 +7,12 @@ then
     echo "    git force <remote> <branch>"
     exit 0
 fi
+git rev-parse --is-inside-work-tree > /dev/null 2>&1
+if [[ "$?" != "0" ]]
+then
+echo "error: not a git repository"
+exit 10
+fi
 REMOTE=""
 BRANCH=""
 PRETTY="--pretty=format:%h, %an <%ae>, %cr: %s"