Selecting a project delivery system is widely understood to be part of the project definition phase. That selection is made from a finite set of alternative contract and phase structures; e.g., design-bid-build or design-build. In this paper, we explore two alternatives to the received wisdom; namely, 1) project delivery systems are products of design, not simple selection, and 2) for best outcomes, project delivery systems are designed to align interests, integrate specialists organizationally, and to be executed using a Management-By-Means philosophy. We argue that these features of project delivery systems are the more needed as projects become more complex and uncertain. We further explore the limits of design on complex, uncertain projects, and the need for in-process management that is nimble and opportunistic. Case studies are advanced in explanation and as evidence for our claims.