Designing urban transit systems: an approach to the route-technology selection problem. Paper presented at the 51th Annual Meeting Highway Research Board HRB, Washington, D.C., January 1972.

The Service Specification model is a tool for generating and screening public transportation systems. The model is based on the concept of a service specification or supply-function which integrates hardware system attributes and operating policy. The model appears to a useful tool for generating alternative transport systems based on different technology mixes and operating policies in any transportation context for which a service specification can be formulated.