The Federated Society of Electrotypers, Stereotypers and Assistants was established in 1893, although a local trade society had existed in London since 1864. It was renamed the National Society of Electrotypers, Stereotypers and Assistants in 1917 and the National Society of Electrotypers and Stereotypers in 1919. In 1967 it merged with the National Graphical Association (NGA).

The Modern Records Centre holds the annual reports of the union's London Branch (MSS.28/ES/4/3/1-4), from which the following information comes. Note that no records of other branches are held.

Full membership lists

The annual Reports include full annual membership lists from 1915 to 1958. These are arranged alphabetically and include only name and union number. On the 1915-1918 and 1939-1945 lists it is indicated whether the member is on active service with HM Forces.

New members

New members are listed annually from 1915 to 1927, including men transferring in from other branches of the union, with name, union number, status (apprentice, probationer or journeyman) and employer.

Lapsed members

Lapsed members are listed annually from 1915 to 1958. Any member who left the London Branch for whatever reason is listed, including those who resigned, 'ran out' (i.e. stopped paying dues), died, emigrated or transferred to another branch. Only name, union number and reason for lapse (including branch transferred to if appropriate) are listed.