Shirley Vivian Teresa Brittain Williams, Baroness Williams of Crosby, was a British Liberal Democrat politician and academic who served in the Cabinet as Secretary of State for Prices and Consumer Protection from 1974 to 1976 and Secretary of State for Education and Science and Paymaster General from 1976 to 1979. Originally a Labour Party Member of Parliament (MP), she was one of the 'Gang of Four' rebels who founded the Social Democratic Party (SDP) in 1981.