Internet users generally feel their actions are anonymous, but this is often not the case. Users can be tracked and their actions logged for future analysis, which is not the desire of most users. Software and services exist which offer anonymity on the Internet when used correctly. Anonymity on the Internet is useful for many people including whistleblowers, dissidents, law enforcement, and the security conscious, but it can be abused. A user can act maliciously under the guise of anonymity without the fear of retribution. Thus, a level of administrative control over users is desirable, even in an anonymous system. Administrative control over users in an open, anonymous system is extremely difficult, but what about a closed, pseudonymous system? Closed Pseudonymous Groups is a pseudonymous framework for a closed group of users that balances the needs of the user with those of a service administrator. Using a resource that uniquely identifies a user, the user may create a pseudonym with which they can interact with the service over the Internet. Misbehaving pseudonyms can be blocked from using the service, and the offending user is unable to create a new authorized pseudonym.