Rails 3 Authorization -

trying figure out how can perform authorization on rails 3 application. using cancan, needed little more complex 1 user role.

my application has user model, project model , project members model. there has many through relationship setup between models. below current schema....

users
- first name
- last name
- email

projects
- name
- active

project members
- user_id
- project_id
- role

when user logs site prompted select project select menu. options in select menu created

current_users.departments.where(:active => true)

after hit submit session variable set session[:department_id]. need find way pull role id user , project , lock down things based on role.

thanks, kyle

i able take care of cancan , of ryan b.