His field of research is Scotland-England relations during the late medieval period (1369-1403), particularly the development of "Frontier societies" and Scotland's place in the wider world during this period. His current research is “to examine the nature and impact of war on state and society in later medieval Scotland”.
He is also a deeply respected and talented cricketer famed for being a combative fast bowling all rounder playing mainly for Aberdeen Grammar School FPs. He once famously claimed a hat trick to defeat Inverurie and has regularly made important contributions with bat and ball and is viewed as a top 1st slip by many. Despite being hampered by injury in recent seasons, MacDonald has still managed to pile on runs in the lower leagues and remains a much feared opponent.