Watson Douglas Buchanan Forbes (16 November 1909 in St Andrews – 25 June 1997 in Moreton-in-Marsh, Gloucestershire) was a Scottish violist and classical music arranger. From 1964 to 1974 he was Head of Music for BBC Scotland.
Watson Forbes was born in St Andrews, where his parents kept a jewellers shop. He first learnt the violin from his father, who was a Scottish country fiddler. Showing promise, at the age of 16 he was sent to the Royal Academy of Music in London, where he studied violin and viola. He gradually specialised on the viola, for both musical and pragmatic reasons. In 1930, he went to Pisek in Czechoslovakia to study with Otakar Ševčík, whose intricate system of exercises revolutionised string playing; he felt he had benefited enormously from this period: "Sevcik taught me how to practise and how to tackle difficult passages." Following this concentration on technique, Forbes had lessons from Albert Sammons. "He was marvellous. He taught me how to perform - how to put music across to an audience."
The invitation to join the Stratton Quartet set the direction of his career. The Stratton was Elgar's preferred quartet, and their recordings in 1933, of his String Quartet and Piano Quintet were the music he chose to listen to on his deathbed. Forbes remained with the Stratton for the rest of its existence as such.
At the start of the Second World War, Forbes was joint leader of the London Symphony Orchestra, but from 1940 onwards he joined the RAF Symphony Orchestra which contained a number of small groups of chamber music players. He toured the UK in a piano quintet which included Denis Matthews, Frederick Grinke and James Whitehead. He also made many appearances in Myra Hess's concerts at the National Gallery. After the war he continued with the Stratton quartet, but now, following the departure of George Stratton, renamed the Aeolian Quartet. He also played with other groups, and as a soloist. In 1954 he became professor of viola and chamber music at the Royal Academy of Music in London.