Engineering System Design has often been treated as an art. Successful practitioners, “old hands” in experience (and often years), produced satisfactory solutions to design problems using principles and rules of thumb which had evolved from many years of practice.Economic solution of the design of complex systems of our present-day industrialized society can only be achieved by a marriage of various numerical adaptive techniques and in a man-machine interactive environment.To this end, our paper discusses the philosophy of good systems design in engineering by describing the difficulties of analytical and numerical solutions, in the presence of a variety of restrictions and constraints, and by giving a general computer-oriented, design procedure.