diff --git a/stack.sh b/stack.sh
index 513f8be..1ee70a6 100755
--- a/stack.sh
+++ b/stack.sh
@@ -89,15 +89,10 @@
 # Sanity Check
 # ============
 
-# We are looking for services with a - at the beginning to force
-# excluding those services. For example if you want to install all the default
-# services but not nova-volume (n-vol) you can have this set in your localrc :
-# ENABLED_SERVICES+=",-n-vol"
-for service in ${ENABLED_SERVICES//,/ }; do
-    if [[ ${service} == -* ]]; then
-        ENABLED_SERVICES=$(echo ${ENABLED_SERVICES}|sed -r "s/(,)?(-)?${service#-}(,)?/,/g")
-    fi
-done
+# Remove services which were negated in ENABLED_SERVICES
+# using the "-" prefix (e.g., "-n-vol") instead of
+# calling disable_service().
+disable_negated_services
 
 # Warn users who aren't on an explicitly supported distro, but allow them to
 # override check and attempt installation with ``FORCE=yes ./stack``