Holden was an experienced architect when he began his Underground work for Pick, though he had never designed for transport. Having worked with Arts and Crafts architect C. R. Ashbee, he joined the practice of H. Percy Adams, establishing his reputation with buildings such as Bristol Central Library and the British Medical Association in London.
Pick and Holden first met in 1915 as founder members of the Design and Industries Association (DIA), a group that brought together artists, architects, manufacturers and retailers intent on improving standards of design in British commerce. In all their work for the Underground they both followed the DIA’s rigorous 'Fitness for Purpose' rule. Pick later commissioned Holden to redesign the facades of several underground stations as well as design a pavilion at the 1924 British Empire Exhibition at Wembley to represent the Underground Group.