Martyn Rowlands trained at the Central School of Arts and Crafts in London. Specialising in plastics, he was one of the first trained industrial designers to work with British industry after the Second World War. He was employed first by Bakelite Ltd., then set up the design department at Ekco Plastics, where his products won a number of design awards. In 1959, he left Ekco to work as an independent design consultant, at a time when the idea of the design consultancy in Britain was still in its infancy. One important commission during this period came from the GPO in 1966 for the popular telephone known as the 'Trimphone', which won a Design Council Award.

During the 1960s and 1970s, Rowlands designed plastics for domestic use for various clients including Insulex, the manufacturer of this insulating double-walled mug.