Sir James Alexander Mirrlees FRSE FBA (5 July 1936 – 29 August 2018) was a British economist and winner of the 1996 Nobel Memorial Prize in Economic Sciences.

Born in Minnigaff, Kirkcudbrightshire, Mirrlees was educated at Douglas Ewart High School, then at the University of Edinburgh (MA in Mathematics and Natural Philosophy in 1957) and Trinity College, Cambridge (Mathematical Tripos and PhD in 1963 with thesis title Optimum Planning for a Dynamic Economy, supervised by Richard Stone).

A contemporary, Quentin Skinner, has suggested that Mirrlees was a member of the Cambridge Apostles along with fellow Nobel Laureate Amartya Sen during the period.

[citation needed] During his time at Oxford, he published papers on economic models for which he would eventually be awarded his Nobel Prize.

Among other results, he demonstrated the principles of "moral hazard" and "optimal income taxation" discussed in the books of William Vickrey.