This article may help. http://msdn.microsoft.com/archive/default.asp?url=/archive/en-us/dnarfoxgen/html/msdn_security.asp?frame=true

>I am trying to come up with a security design scheme for my application. I have a Users table, a Groups tablea and a Rights table.
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>The problem is that it's not just access to specific areas that I need to code for. I also need to allow only certain groups of users access to specific documents.
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>For example, if a sales rep makes contact with a client, the other sales reps cannot be allowed to see that information.
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>Only certain groups of people in the organization can be allowed to see certain data, so I need a way to set this all up in the data.
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>Thanks