A skilled draughtsman who has produced a varied body of work, Knox is known for his sensuous use of colour. In the mid 1960s, he produced his Studio series of canvases using mixed media and ‘stream of consciousness’ imagery. These were followed by square white canvases covered with symbols. However, it was a visit to a Dutch museum that motivated Knox’s subsequent change of artistic direction to produce lusciously coloured images of food. It was the combination of seeing Dutch still life painting and noticing the way that the food in the cafeteria was presented as if framed and on display that provided the inspiration. Knox was born in Kirkintilloch and studied at Glasgow School of Art, where he later became Head of Drawing and Painting.