Sarah Coryton of Pentillie Castle was sworn in as High Sheriff of Cornwall in the grounds of the historic estate near St Mellion.
Previous High Sheriff, Mrs Jane Hartley, handed over her badge of office.
Sarah is the tenth High Sheriff of Cornwall connected with the Pentillie estate, and will be the 12th female in the office.
She is looking forward to working with local crime prevention agencies, the emergency services and the voluntary sector, supporting the Crown and the judiciary.