I'd like to create several restricted user groups with each group having access to the groups below it:

level 1: secret
level 2: top secret (with access also to 'secret' articles and modules)
level 3: top top secret (with access also to 'secret' and 'top secret' articles and modules)

I found this tutorial for Joomla. Does K2 have an equivalent tutorial?
docs.joomla.org/J2.5:Access_Control_List_Tutorial

Thank you

Hello Ken,

K2 inherits Joomla!'s user permissions but also has it's own user groups for functions like commenting or front-end editing.

For what you want to achieve I would use default Public, Registered and Special access levels provided by Joomla!

I cannot use just public/registered/special as I may need many many more permission levels as this is a very large university website.

Any suggestions? Perhaps a third party software?

thank you

Yes, you have to create new Joomla! user groups and new access levels (eg. above or between super user ).

Then all you have to do is choose the appropriate Access level for each K2 item. No additional extensions needed :)

In your position I d setup a test Joomla! site and play around a bit with access levels and new user groups.