In the early 1980s Christopher Wright began work with Catherine Gordon at the Courtauld Institute on an index of British and Irish paintings in Public Collections. Together they collected lists and information about public collection holdings across the country. By 1998 the project had fallen into difficulties and it was taken in-house by the Paul Mellon Centre.
The information received from the various institutions contacted was added to a database. Between 1998-2000 this work was undertaken by Matthew Imms. From 2000, it was continued by Mary Peskett Smith. As there were discrepancies, some of the institutions were contacted again, which resulted in the production of new lists of holdings. All the information received was collated to produce the book 'British and Irish paintings in public collections: an index of British and Irish oil paintings by artists born before 1870 in public and institutional collections in the United Kingdom and Ireland', published in 2006 for the Paul Mellon Centre for Studies in British Art. The publication encompasses nearly 9,000 painters and 90,000 paintings in more than 1,700 separate collections.