The World Science Fiction Society (WSFS) is an unincorporated literary society whose primary activity is the running of the World Science Fiction Convention (Worldcon). Specifically, according to the WSFS constitution [1], its duties are:
WSFS's membership is comprised of the members of the current Worldcon, if one is in progress, or the next one, if not. Worldcons are obligated to host the annual WSFS business meeting.