diff --git a/scripts/tidy_filenames.sh b/scripts/tidy_filenames.sh
index f500064..b2fce69 100755
--- a/scripts/tidy_filenames.sh
+++ b/scripts/tidy_filenames.sh
@@ -4,7 +4,7 @@
 
 main() {
     find . -depth -name '*-*' -name '*.md' | while read fname; do
-        new_fname=$(echo $fname | tr "-" "_")
+        new_fname=$(echo $fname | tr " " "_" | tr "-" "_")
         if [ -e $new_fname ]; then
             echo "File $new_fname already exists. Not replacing $fname"
         else