After a 20-year medical career as a medical doctor in the field of (in)fertility, Kees started a new career in the early 90s. He enrolled in the arts program at Ars Aemula Naturae in Leiden, Holland. Since then his painting style has developed into a style between impressionism and expressionism. In 2000,  Kees started cooperating with fellow-artist Robin Akkerman. Together they paint large canvases with anecdotal themes.