With the increasing development of new vehicles with advanced powertrains, and the increasing prominence of energy and environmental considerations, sophisticated computer aided analysis and design tools are rapidly becoming essential. Computer aided engineering (CAE) in automotive applications has gradually extended its boundaries beyond geometrical modelling, finite element techniques, and drafting, into automotive engine management and driveline control. In this particular area of activity the CAE techniques proving most useful are static and dynamic systems modelling and simulation, and control systems synthesis and optimisation. The main emphasis in this thesis is in the area of modelling and simulation of vehicles for addressing problems of emission constrained fuel economy optimisation. In order to place engine control system optimisation in context an assessment of the development potential of automotive systems, with regard to fuel economy improvements, is undertaken. Some important aspects of the modelling of automotive systems are addressed, with particular relevance to emission constrained fuel economy problems. A dynamic simulation facility, based on this modelling, is developed for use in the preliminary evaluation of control strategies. The thesis reports on an application of this facility to the study of an engine calibration procedure intended for on-line optimisation of the dynamic system; and also to the study of a simple extremum-seeking adaptive ignition timing controller. The simulation facility proved useful in the study of these two different types of control procedures, but more importantly, served as a means of identifying the more general requirements associated with the use of continuous dynamic simulation in the context of automotive control system development. Finally, recommendations are made for the development of an integrated CAE environment for use by automotive systems engineers. These recommendations are based on the diverse requirements of the data handling, modelling, and simulation activities encountered during the course of this study.