Correspondence between Thomas Henry Huxley and Henrietta Anne Heathorn, 1847-1854, written during their engagement whilst Henrietta was living in Australia, and providing a detailed account of their relationship.

Papers of the Group Relations Training Association (GTRA), 1971-2001, comprising GTRA publications including leaflets; fliers for special events, 1983-1990; Annual General Meeting notices and reports, 1983-1986; Calendar of Events, 1983-1986; Newsletter, 1973, 1983-1992; conference fliers, 1983-1984 and 1993-1994; Annual Training Laboratory fliers, 1983-1991; Bulletin, 1976-1988; 'Group Relations', 1989-1992 and 'The Groupvine', 1992-1995. Papers relating to conferences, mainly comprising committee minutes, planning materials and conference notes, 1971-1988. Papers relating to the Training Labs including on finance, correspondence, membership and applications, 1981-1995. Papers relating to the Executive Committee including minutes and papers on membership and publicity, 1971-1989. Papers on GTRA events including 'The gift relationship', at Beechwood College, Leeds, 1981; 'Women and men' workshop, 1981; 'Mini-Society' event at Beechwood College, Leeds, 1983; 'Mini-economy' event at Beechwood College, Leeds, 1985; 'Mini-economy II' event, 1986 (cancelled) and Berlin Summer School ('Men and women in groups'), 1987. Cassette tapes, including of an interview with Cary Cooper on T groups, 13 Mar 1986; a GRTA Workshop, 2 Sep 1983 and a rehearsal for GRTA Conference, 1985. Academic papers on training groups including PhD thesis by Nod Miller 1989, 'Personal experience, adult learning and social research: developing a sociological imagination in and beyond the T-Group' (University of Manchester) and MSc in Group Relations thesis by Guy Marsden Wareing 2001, 'Pilgrim's Process: making sense of experiential group events through narrative accounts of participants' (University of the West of England, Bristol).