'The Wardrobe' building and its grounds were leased from the Salisbury Cathedral Authorities for 99 years from 29 September 1978 by a charitable trust set up by The Duke of Edinburgh’s Royal Regiment (Berkshire and Wiltshire), in order to house the Regimental Headquarters and Museum and to host Regimental events. The project was financed in large part by individual donations from serving and retired members of the Regiment, of all ranks, and from former members of The Royal Berkshire Regiment and The Wiltshire Regiment which had amalgamated on 9 June 1959 to form DERR, as is indicated by the badges on the building.
On 27 April 1994, the Regiment amalgamated with The Gloucestershire Regiment to form The Royal Gloucestershire, Berkshire and Wiltshire Regiment. On 22 July 2005, RGBW was incorporated into the Light Division and retitled The Royal Gloucestershire, Berkshire and Wiltshire Light Infantry. On 1 February 2007, RGBWLI merged with the other three regiments of the Light Division to form The Rifles, and the regular battalion of RGBWLI combined with that of The Devonshire and Dorset Light Infantry to form the 1st Battalion of the new Regiment of five regular battalions.
The Wardrobe remains the spiritual home of both DERR and its successor regiment RGBW/RGBWLI and a base for The Rifles to maintain its links with the counties of Berkshire and Wiltshire. It is the responsibility of The Rifles Wardrobe and Museum Trust, Registered Charity No 272051, which wholly owns The Rifles (Berkshire and Wiltshire) Museum.
As far as the Museum is concerned the Trust principal object is to provide and maintain a public musuem for the exhibition to the public, of documents, artefacts and other items connected with the former regiments (the Regimental Collection) so as to educate the public and members of the former regiments in the history of the former regiments and to promote military efficiency.