Lastly, the organizer of a tournament will have the option to require approval for new participant registration when a tournament is already under way. This approval process could be carried out by an organizer, a moderator, or a participant, and the system can have a specific internal role which would allow users involved in a tournament to have approval rights. This could be as simple as only allowing organizers to approve registrations, in this case any invitations sent by regular participants would need to be approved by an organizer), and we feel that the system should encourage the organizer to choose this option, since it adds a strong quality control mechanism to the participant pool.