Colombo initially trained as a painter and joined the Nuclear Painting movement before studying architecture at the Milan Politecnico. In 1962, he opened his own design office and led progressive Italian design with a series of products in new materials, mostly in plastics. He received many awards, among them two Compasso d'Oro in 1967 and 1970. His design innovations included one of the first one-piece injection-molded plastic chairs and a complete kitchen on wheels. Colombo worked for Bayer, Bernini, Kartell, Stilnovo, O-Luce, Comfort, Italora... Many of his works have been exhibited and included in the most important Museums's collections all over the world.