Ian Malcolm Bowen Stuart (18 September 1902 – 3 August 1969), known as I. M. B. Stuart, was an Anglo-Irish schoolmaster, author and broadcaster in the United Kingdom who migrated to the United States in 1946. In 1924 he played rugby for Ireland and also for the British Lions, and he later taught and wrote extensively on the game, which he introduced to Harrow School in 1927.