Following the pre-legislative Welsh devolution referendum of 18 September 1997, Royal Assent was given on 31 July to the Government of Wales Act 1998. This created the National Assembly for Wales, to which overall responsibility for NHS Wales was devolved in 1999. Responsibility, therefore, for NHS Wales was passed to the Welsh Government under devolution in 1999 and has since then been the responsibility of the Welsh Minister for Health and Social Services.