Artist, print maker, designer, and arts administrator. McNab studied at the Royal College of Art in London and the Ecole des Beaux-Arts in Paris during the 1920s. He produced a small body of prints during the 1920s and early 1930s before becoming a design director for Norman Bel Geddes from 1938-1945. He later became an art director for Life Magazine before working in art museum administration as director of the Lowe Gallery at the University of Miami and Director of Administration at the Art Institute of Chicago. McNab exhibited his prints at the Royal Academy, the Royal Scottish Academy, the Royal Society of Painters and Etchers, and other venues. His work is major collections such as the British Museum, the National Gallery of Canada, Cornell University, Princeton University, and others.