Christopher Addison enjoyed two careers, one as an anatomist followed by that as a politician. He described the detailed topographical anatomy of the abdomen, and his name is associated with one of its key anatomical planes. His political career was influenced by his commitment to social reform and for the need for improvement in public health achieved through government intervention. He held several ministerial offices, and he was the first Minister for Health. He played important roles in the passage of the National Insurance Act 1911 and introduced the Housing and Town Planning Act 1919. Following the Second World War, he was responsible as Leader of the House of Lords for the passage of legislation including that related to the formation of the National Health Service.