This article examines the roles played by the conservation profession during periods of looting by the National Socialist German Workers Party. Research was carried out to establish the extent of the involvement of conservator/restorers and how specifically their expertise was utilized. Primary documents and other materials relating to American interrogations, seized Nazi documents and other papers held by descendants were used during research. The paper concludes that the looting process, selling on of works and setting up of collections would have been more difficult and slower in process without the use of conservation professionals. The article uses the word ‘restorer’ rather than ‘conservator’ to avoid anachronism and reflect the early 20th century usage. Some restorers mentioned in interrogation reports are only mentioned by surname. The precise identity of those concerned has not been fully resolved in all cases.