The papers of Peter Tatchell includes correspondence, newspaper and magazine articles, press releases, posters, leaflets and publications on the following topics: Aids/HIV research, vivisection and animal rights, homophobic violence and policing, the age of consent, media portrayal of homosexuality, negative comments on sexuality by 'personalities', homophobic lyrics and the music industry, international politics, green socialism, Labour and politics, Members of Parliament and 'outing', the Bermondsey By-election, the Greater London Assembly, Christian, Jewish and Islamic leaders' stances on homosexuality, the law and sexuality, the prosecution of homosexual acts, and the employment of homosexuals in the armed forces.

The archive consists of memorabilia of suffrage activities including press cuttings, objects and hunger-strike medal; publications and manuscript material on the ordination of women and animal protection; correspondence; correspondence from Hove Borough Council relating to a commemorative plaque and photographs.

Papers of the Research Defence Society, 1811-1992, comprising papers; administrative records; correspondence; minutes; records of membership, meetings and rules; annual reports; treasurers reports; accounts; RDS publications including Conquest magazine (which was called The Fight Against Disease until 1950); copies of Acts of Parliament, Bills and Royal Commissions, 1786-1915; correspondence and papers relating to animal rights Bills, 1927-1937 and 1965-1980; literature and publications used by the RDS; anti-vivisection literature; newspaper cuttings; tape recordings and films; and photographs and slides.