(1) A Convention-Running Organization
(2) A Boston Convention Center
The Boston Convention and Exhibition Center is Boston's newer and larger (newer and larger than the Hynes Auditorium that the Noreascons have used) convention center located in South Boston next to the Westin Waterfront.
It is generally judged to be a substantially worse facility for Worldcon needs than the Hynes Auditorium due to its somewhat isolated location, awkwardly large size — far too big for a Worldcon — and function space which is generally not a good match for Worldcon. (It's really aimed at hosting things like boat shows which need a huge open exhibit floor.)