Born in Glasgow in 1950, Forrest attended Glasgow School of Art between 1969 and 1973 prior to becoming a tutor there for seven years. In 1985, he gave up his teaching so that he could devote his time to painting. Forrest was elected a Member of the Royal Glasgow Institute of the Fine Arts in 1988 and has been a regular exhibitor there and the Royal Scottish Academy since 1975. He has won numerous awards for both his painting and sculpture. Examples of his work can be found in private and corporate collections worldwide.