Best setup for multi author site, roles

Hi, I am in the process of setting up a multi user site and need some advice on roles and functions, and suggestions for any plugins that will help.

I currently have 3 user levels:

Admin – web developer – global access

Department director – contribute ext and approve posts and pages suitted for review by level 2 staff. When something is pendig review, needs email notifier, and ability to modify, approve and post.

Department staff – contributors of articles

My question is can I do this with the default wordpress setup or do I need a plugin?

Thanks!