You need to use the System.DirectoryServices namespace. Here is an article that you might find useful:

http://www.15seconds.com/issue/020730.htm

>Hi,
>
>Via VB.Net I need to retrieve a list of domain users (in "regular" WINNT/W2K or in Active Directory). I just need the user login, first name, last name (no password or other security info).
>
>Can I do this ???
>
>TIA !!!
>
>Best Regards,
>Jace