Alasdair Donald MacDuff Liddell CBE (15 January 1949 – 31 December 2012) was one of the architects of Britain's health strategy in the 1990s. As Director of Planning at the Department of Health (1994–2000) he led the process of setting national priorities for the National Health Service (NHS). He died at age 63 of an aneurysm he suffered while visiting friends in London.