Engineering products (designs) are developed from a product idea or from given requirements (a design brief) in a process called designing. The product realization process is often preceded by product planning, and continues after designing with manufacturing, distribution, sales, etc. Even though intuition, experience, teamwork and human qualities of designers play a large role in designing and need to be investigated, rationalization and systematization is possible and desirable, both in the procedures and in the progress of the system being designed. Stages of designing include clarifying the problem, conceptualizing, embodiment and detailing. Designers must consider the requirements of all other life stages of the product along with societal and ethical considerations. It seems preferable to spend more time on the preparatory early stages, rather than correcting problems in later development phases. Methods to perform parts of the main stages, and coordinated forms of modeling, have been reported and collected. A near-optimal solution proposal can emerge because several alternative solution proposals can be generated, unsuitable alternatives can be eliminated and errors cart be found and corrected early in the process. The models exist at several levels of abstraction. Progress through these levels using the available methods allows a systematic search for solutions in a wide field, while limiting the potential for combinatorial complexity. The methods and models have been brought into the framework of a comprehensive theory-design science-which coordinates the progressive development of the future product with the theory. With these claims, it may be surprising that industry does not use these methods. An explanation for this delay is offered.
