The Trust was formed in 1967, its purpose being "to preserve property and buildings of architectural and historical interest in the county for the benefit of the nation". It is both a registered charity and a company limited by guarantee. The money employed by the Trust originated in a single grant made at the time of its foundation by the former Wiltshire County Council, funding which has been described by the Trust's President Lord Lansdowne as "a revolving capital sum". Since 1967, the Trust has been instrumental in a number of projects for the restoration and conversion of historic buildings large and small. At the end of a project, the restored building is sold, so that the Trust can recover the money laid out and look for a new project. The restoration projects of the charity have included the following buildings: Barton Farm, Bradford on Avon ; Number 23, South Wraxall ; Wilton Windmill, near Marborough ; Number 3, High Street, Marlborough; Numbers 7, 9, 11, 13, 15, 21, 23 and 25, Church Street, Calne ; The Well House, Derry Hill ; The Ostler's House, at the Hare and Houndspublic house, Pickwick ; The Apple Store, Rowdeford School ; and The Granary, Manor Farm, Yatesbury. Given its planned nature as a revolving fund, the articles of association of the Trust prevent it from making grants to private owners of historic buildings, but it has sometimes made contributions to special projects around Wiltshire promoted by others. A loan was made to the Merchant's House Trust in Marlborough to enable it to buy the burgage plot associated with the Merchant's House. Grants have included one to the Warminster Buildings Preservation Trust for a town centre project, another to the Friends of Lydiard Park to help with the restoration of an ice house in the grounds of that country house, and a contribution was made to the Salisbury Cathedral Appeal. The Trust is a member of the Association of Preservation Trusts.
Devizes Assize Courts
After becoming redundant in the 1980s, the Grade II* listed former assize court building – built in 1835, in Grecian style using Bath stone to designs of T. H. Wyatt – stood unused. The Trust assisted Kennet District Council with a study in 2006–7, and in 2018 supported the establishment of Devizes Assize Court Trust, a charity which bought the building and aims to restore it to provide a new home for Wiltshire Museum.
The Trustees are known as 'Governors'. Four are appointed by the Wiltshire Councilunitary authority, and one by the Borough of Swindon; other new Governors are appointed by the existing Governors of the Trust.
