I was working on [this][1] yesterday and a user suggested that I use `PrincipalSearcher`. I am altogether new to this concept so I tried looking around for a tutorial on this just as a starter point and could find no working solution but here is what I have learned:
1.) I know that I want to be using the following namespaces:
using System.DirectoryServices; using System.DirectoryServices.AccountManagement; 2.) I know that I would use `PrincipalContext` instead of `DirectoryEntry` as in:
PrincipalContext = new PrincipalContext(ContextType.Domain, “Domain.com”);
By using this I can filter down into an OU by using GroupPrincipal.FindByIdentity
var principal = GroupPrincipal.FindByIdentity(context, “Physicians”); I just don't know how to fit it alltogether. For instance lets say that I have a simple form: 
<asp:TextBox id ...

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