The aim of this research has been to find a valid and practical model upon which to base a computerized support tool for the conceptual stages in engineering design. In the event, this work expanded to the point where a generic computational support environment known as the conceptual design support and analysis system (CODSAS) was constructed, providing an integral, consistent, domain-neutral framework for carrying out conceptual engineering design. Domain neutrality is assured by means of a novel customization facility provided through appropriate implementation of a new high-level programming language called design procedures programming language (DPPL) which has specifically been created to define chosen procedural models of engineering design. Therefore, CODSAS is capable of a very large variety of conceptual design activities, based on specialized tools, and provides contextualized and task-appropriate support for the creative designer to work within a flexible methodology-based computational framework. In addition to being a design support system, CODSAS can be used as a testbed for design research, given its ability to capture the design history (rationale), the frequency (how many) and the duration (how long) of design tasks.