I am looking for a way to have a subforum that is only visible to selected persons. I searched on this but what I found was making the entire forum private, which I do not wish to do. Help?
look up subcategories, and roles and permissions.
grep is your friend.
Put the selected persons into a new role.
Edit the private category and make sure "This category has custom pemissions" is checked.
Give the new role permissions, and take it away from the others.