Attending classes is generally restricted to Brown students or officially enrolled non-degree students who are registered participants. A student who has requested and been granted the instructor's permission for "vagabond" status in a course is an exception. With permission or an invitation from the instructor, a visitor may attend class with a Brown affiliate, a current student or a faculty member. Any other visitors to the campus who would like to sit in on a class must register with the Office of Admissions in advance and seek permission from the individual instructor. This permission will be granted at the discretion of the instructor.