Whitelisting instead of Blacklisting

[Stewart]

What's the best method to whitelist instead of blacklist? I would think it's an alias I can select for the Source Address but the alias doesn't appear until I do something with it in pfBlockerNG. (I'm using -devel).

For example, I'd like to white-list North America, specifically just the United States, for users to connect in as they travel around the country. I go into the list and select United States but what about List Action? I'm missing a step and need some guidance. Thanks.