Focussing on the Duchy of Cornwall’s organisational structure during the Wars of the Roses, this survey examines the principal offices (which evolved around administration of its marine and terrene regalities) and personnel (administrative elite) in Cornwall and Devon. Consideration of successive Princes’ Councils and counsellors (and Councils of Wales and the Marches) leads onto exploration of the roles of various courtiers, magnates, and royal household servants in the affairs of the Duchy and the wider implications – for south-western England – of Duchy service.