Papers of Howell T. Evans, 1877-1982, including family and general correspondence, 1904-1949; diaries, 1899-1936; diaries of Mrs Gwenllian Evans, 1936-1938; newspaper cuttings of reviews and articles, 1899-1934; publishing contracts and related papers, 1907-1938; notes for radio broadcasts and entries in the Dictionary of Welsh Biography, 1945-1949; biographical material, 1877-1978; list of books published, 1908-1934; printed material, 1916-1956; and items relating to Portrait of a Pioneer, [1982].

Research papers of Wynford Davies, 1961-1980s, mainly on educational matters, including notes compiled by him in preparing his book, The Curriculum & Organization of the County Intermediate Schools, 1880-1926 (1989); research papers on intermediate education in Wales, 1970s-1980s and correspondence on small rural schools, 1961-1966.

Cofnodion Pwyllgor Datblygu Addysg Gymraeg, PDAG, 1985-1994, yn cynnwys cofnodion cyfarfodydd, gohebiaeth, adroddiadau a deunydd ymchwil, gyda phapurau sydd yn ymwneud gan fwyaf â'r sector addysg yng Nghymru (ysgolion, prifysgolion a cholegau, ac addysg i oedolion) ac â chyrff megis y Swyddfa Gymreig, Bwrdd yr Iaith Gymraeg, Cyngor Cwricwlwm Cymru, Cydbwyllgor Addysg Cymru, Rhieni dros addysg Gymraeg, ac amryw gynghorau sir yng Nghymru = Records of the Welsh Education Development Committee (Pwyllgor Datblygu Addysg Gymraeg, PDAG), 1985-1994, including minutes of meetings, correspondence, reports and research material, with papers mostly relating to the Welsh education sector (schools, universities and colleges, and adult learning) and to bodies such as the Welsh Office, the Welsh Language Board, Curriculum Council for Wales, the Welsh Joint Education Committee, Parents for Welsh medium education, and to various county councils in Wales.