Education
Sumner studied History of Art at the Courtauld Institute, University of London, and obtained a Doctor of Philosophy in History from Newnham College, University of Cambridge.
Sumner studied History of Art at the Courtauld Institute, University of London, and obtained a Doctor of Philosophy in History from Newnham College, University of Cambridge.
She was the executive director of the Brontë Society, a former director of the Barber Institute of Fine Arts at Birmingham University, England (2007–2012), and the first director of the Birmingham Museums Trust, comprising the merged Birmingham Museum and Art Gallery and Thinktank, from 2012 until 2013. She started her career at the National Portrait Gallery, London and has held curatorial positions at the Whitworth Art Gallery, Dulwich Picture Gallery, Harewood House, and the Holburne Museum, Bath. Before her directorship at the Barber Institute, University of Birmingham, she was Head of Fine Art at National Museum Wales, for seven years (2000–2007).
In 2007 she became Barber Professor of Fine Art and Curatorial Practice and remains Visiting Professor.
Her specialist areas of interest are 17th-century British portraiture and miniature painting, 18th-century British portraiture and landscape painting, French 19th-century painting, the art of Wales and has long had an interest in art inspired by the game of lawn tennis. She is currently researching public art by the American sculptor Mitzi Cunliffe in the 1950s.
She is currently Historic Collections Adviser to the Harewood House Trust.
She was a founding member of the Steering Group for Pre 1900 European Paintings Specialist Subject Network, is a Trustee of the Methodist Art Collection of Modern Art, was a member of the panel from the Leverhulme Art History Prize 2010/11, and sits on the Curatorial Advisory Group for the Ironbridge Gorge Museums and is a member of the Advisory Committee for the School of Art Gallery & Museum, Aberystwyth University.