php cookies block access to directories

I have a mysql database of users that can login to my site and view content. I would like to block a couple of directories from certain users. What is the best way to do this.

Currently when a user logs in a cookie is created with their customer id and th开发者_如何学JAVAe customer is is used to display their content.

How would I block entire directories from my users???

EDIT: I need to allow one user in my database to access the directories once logged in.

See:

Mod_rewrite - Deny access to certain folders

More Info:

http://www.askapache.com/htaccess/mod_rewrite-tips-and-tricks.html