Building Societies Act 1986 - registration as a building society.
Industrial and Provident Societies Acts 1965 to 2003 - registration of co-operatives and community benefit organisations. See http://www.hm-treasury.gov.uk/consultations_and_legislation/creditunions/consult_creditunions_index.cfm for consultation on reforms to this legislation
Friendly Societies Acts 1974 and 1992 - registration as a friendly society for mutual insurance of the members.
The Companies (Audit, Investigations and Community Enterprise) Bill 2004 – the Community Interest Company (CIC) a special type of company – Davies and Gower p p 7-11