Architect and Planner, Founder, Donald Insall Associates Ltd
Founded practice in 1958 (Chairman 1958–1998), now Consultant
- Member of the UK Council, the International Council on Monuments and Sites.
- Member of Advisory/Fabric Committees, Westminster Abbey, and now Southwark and Canterbury Cathedrals. Member of Architectural Advisory Committee, the World Monuments Fund (UK).
- Vice President (1994–), The Building Crafts and Conservation Trust (previously Trustee from 1990 to 1993).
- Council Member, the Society for the Protection of Ancient Buildings (1979–2005).
- The European Commission: Expert Committee on the European Architectural Heritage, Brussels.
- President (1994): the Association for the Study of the Conservation of Historic Buildings (ASCHB).
- Architect Member of HM Government Inquiry: Fire Safety in the Royal Palaces (1993).
- Founder-Commissioner, The Historic Buildings and Monuments Commission (English Heritage); and Member of the Commission’s Historic Buildings Advisory Committee and Historic Areas Committee (1984 to 1989).
- Patron: the Bedford Park Society; the Kew Society, the Environmental Trust for Richmond-upon-Thames.
- “The Care of Old Buildings Today” (1972)
- “Living Buildings. Architectural Conservation: Philosophy, Principles and Practice” (2008; reprinted 2018)
- D.Arch (University of Chester) 2012
- LL.D. (Bristol) 2004
- The Royal Warrant Holders: Plowden Medal 2001
- APT International: Harley McKee Award 2000
- Europa Nostra Medal of Honour 2000
- RICS People in Conservation Medal 2000
- Honorary Freedom: The City of Chester 1999
- RIBA Neale Bursar 1955
- Banister Fletcher Medallist 1949
- Knighthood 2010
- CBE 1995
- OBE 1981
- The Queen’s Silver Jubilee Medal 1977