Let's say you want to assign some global `ARG` as the default `ENV` when you don't get `ENV` when running a container you can do this ```dockerfile # ---- Global Variables ---- ARG RELEASE_ENV="preprod" # ---- Base Node ---- FROM node:14-alpine AS base # ---- Release --- FROM pre-release-$RELEASE_ENV AS release ARG RELEASE_ENV ENV APP_ENV=$RELEASE_ENV ``` Here, in the `pre-release$RELEASE_ENV`, you assign the global RELEASE_ENV value to the stage and assign this to `ENV`. you cannot directly access global `ARG` inside a stage