The consideration of manufacturing objectives at the design stage is a real possibility given the recent availability of solid modellers within Computer Aided Design (CAD) systems. However, designers and engineers can experience difficulty in communicating with these CAD systems because of the mathematical language which is often used. The ability to capture and transfer design information pertinent to manufacture is also generally rather limited. This thesis describes the development of a language that uses familiar engineering terminology to specify solid models of engineering components. The descriptive nature of the language naturally incorporates information useful to 'downstream' manufacturing functions; an example of process planning for turning is included. In order to test the principles proposed a questionnaire was administered to fifty experienced engineers from a wide range of disciplines. The findings of this questionnaire are presented.