The collection offers a glimpse into the world of a maritime organizer's life during the late 1940s. The bulk of the material spans from 1940 to 1950. The collection contains log sheets and records of Santos' visits on board ships that had been organized by the M.E.B.A, notes from his time as a union organizer, and numerous agreements, both in draft and complete forms, which cover the M.E.B.A. and other maritime unions like the National Maritime Union (N.M.U.) and the Masters, Mates, and Pilots (M.M.P.). The collection does not include complete records for any M.E.B.A. Local or the International. Instead, it offers pieces from a number of M.E.B.A. Locals. It includes constitutional drafts from Locals 97 and 33, meeting minutes from Local 97, and information on affiliation and mergers at the National level. The collection also includes a number of individual copies of newsletters and periodicals produced by various M.E.B.A. Locals, maritime unions, and other labor organizations.