Design and engineering have worldwide impact. The products and systems generated affect every level of our lives. In a competitive world where the prosperity of local industry waxes, wanes and emerges in new forms, temporal strategies and policies for survival and gain inevitably emerge. It is in this context that engineers and designers operate their exciting trades, with consideration of multiple functional attributes in any given application. This may involve attention to technical, aesthetic, economic, social and latent function and their often complicated interrelationships, with one attribute affecting the performance of others in a significant manner. The value of each attribute needs to be maintained at the design stage in order to deliver worldwide competitive products, systems and services. It is in the conceptual, detailed design, fire-fighting and application phases that engineering analysis shows its potential, time and time again, to deliver order-of-magnitude as well as validated estimates for quantities. The tools of engineering provide essential input and infl uence for the design process. These tools can be operated with diligence and exacting analysis, as well as in the fast-paced conceptual stages of any project, in order to explore the what if and to provide a physical basis for an idea, as well as the impetus to give that idea the justification for the resources it requires for elaboration. © Manchester University Press.