He read Medieval and Modern Languages (French and German) at Trinity College, Oxford, including a year at the University of Vienna (BA 1980, MA 1983).
[3][4][1] From 1980 to 1988 he worked in the drawings collection and library of the Royal Institute of British Architects (RIBA) before being appointed Librarian, then Head of Education and Research, at the new Design Museum before its opening in 1989.
He has also sat on the Church Buildings Council and chaired their Sculpture & Furnishings Committee.
He has contributed sections on architecture and the built environment to successive volumes of the Victoria County History of Essex.
[8][9][1] With Graham Watts, Julia Abel Smith, Roy Clare and Juliet Townsend, Bettley formed the Essex Women's Commemoration Project which aimed of identifying distinguished Essex women who had not received the public recognition it was felt they deserved.