Alan Mercer (22 August 1931 – 9 July 2014) was a British emeritus professor of operational research (OR) at Lancaster University until his retirement in 1998. Mercer was one of the founding members of the Department of Operational Research at Lancaster in 1964, the first such department in Britain. He was also a founding editor of the European Journal of Operational Research (EJOR) in 1975, resigning from editing in 1998.