 In 1942, Mackenzie Stuart joined the British Army, becoming commissioned in Royal Engineers and went up to Sidney Sussex College, Cambridge, on the War Office Engineering Course, followed by service, mainly building bridges, in Northern Europe.In his speech on retirement from the Court of Justice in 1988, he spoke of the indelible effect at an impressionable age of seeing the ashes of the Ruhr.After a staff post in Burma and a spell dismantling mines on the Northumbrian coast, he returned to Cambridge University where he resumed his Law studies, taking first class honours in Part II of the Law Tripos in 1949, followed by an LL.B.