Purpose -ASLIB -the Association of Special Libraries and Information Bureaux -was founded in 1924 with the aim of co-ordinating the activities of specialist information services in the UK. This article seeks to present a new history of the first quarter-century of the Association. Design/methodology/approach -This is a historical study based substantially on two collections of primary documents: ASLIB's own records, held at Aslib Headquarters, London; and the papers of Edith Ditmas, held at the National Library of Wales. Findings -The paper explores the origins of ASLIB, and its roots in the "science lobby" of the time; it then traces the development of ASLIB as both a "national intelligence service" for science, commerce and industry, and as a quasi-professional association with international significance. It concludes that the first of these two functions was the Association's fundamental raison d'être.Research limitations/implications -The research is limited to study of ASLIB in the period 1924-1950 and an obvious continuation would be a history of "corporate" ASLIB . More generally, the paper reveals that the history of UK documentation and information science in the twentieth century is underexplored: there is scope for future research focused on key pioneers and ideas, as well as institutions such as ASLIB. Originality/value -As far as is known, this is the first historical study of ASLIB to be based on contemporary records: it should therefore be of value to both historians of information and library science and practitioners interested in their professional heritage.