I'm trying to figure out how to do roles/permissions in our application, and I am wondering if anyone knows of a good place to get a list of different permission-based authorization systems (preferably with code samples) and perhaps a list of pros/cons for each method.

I've seen examples using simple dictionaries, custom attributes, claims-based authorization, and custom frameworks, but I can't find a simple explanation of when to use one over another and what the pros/cons are to using each method. (I'm sure there's other ways than the ones I've listed....)

I have never done anything complex with permissions/authorization before, so all of this seems a little overwhelming to me and I'm having trouble figuring out what what is useful information that I can use and what isn't.

What I DO know is that this is for a Windows environment using C#/WPF and WCF services. Some permission checks are done on the WCF service and some on the client. Some are business rules, some are authorization checks, and others are UI-related (such as what forms a user can see). They can be very generic like boolean or numeric values, or they can be more complex such as a range of values or a list of database items to be checked/unchecked.

Permissions can be set on the group-level, user-level, branch-level, or a custom level, so I do not want to use role-based authorization. Users can be in multiple groups, and users with the appropriate authorization are in charge of creating/maintaining these groups. It is not uncommon for new groups to be created, so they can't be hard-coded.