The University of Michigan Gilbert and Sullivan Society, more commonly referred to by its acronym, is a community/campus volunteer theatrical group that performs only the operettas of the British playwright/composer duo Gilbert & Sullivan. As there are only around a dozen such works, and the group performs two to three shows annually, most Society members are familiar with the entire canon. Shows are performed in the Lydia Mendelssohn Theater in the Michigan League, typically the week after Thanksgiving and the first week of April.
The 2006-2007 season is UMGASS's 60th anniversary, and the spring show features a number of special events for UMGASS members, alumni, and friends.
The related group FUMGASS ("Friends of ...") performs numerous functions, such as publishing the periodical GASBAG ("Gilbert and Sullivan Boys and Girls") and providing scholarships to UMGASS members.