# PRAW Environment Variables

The highest priority configuration options can be passed to a program via environment variables prefixed with `praw_`.

For example, you can invoke your script as follows:

    praw_username=bboe praw_password=not_my_password python my_script.py

The `username` and `password` provided via environment variables will override any such values passed directly when initializing an instance of `Reddit`, as well as any such values contained in a `praw.ini` file.

All Configuration Options can be provided in this manner, except for custom options.