Numerous space projects are underway worldwide which, in the long run, intend to further expand humankind's reach into space and to accelerate the discovery and utilization of resources there. Specific initiatives involving extensive human space activity have been proposed by the US, USSR, European Space Agency and Japan, particularly in Earth orbit, on the Moon and at Mars. As an integrated whole, these proposals suggest an increasing demand for launch systems, upper stages, maneuvering and orbit transfer vehicles of all kinds, and significant increases in total habitable volume in various orbits and extraterrestrial surfaces. There is one critical flaw in all of this, however, that is choking progress every step of the way: the space infrastructure has no architecture; it has no conceptual integrity.This paper addresses the top-level, all-encompassing subject of architectures for utilizing the environment of space - architectures not just for space stations, launch vehicles or human outposts, but for the entire space systems infrastructure. Functional requirements for a sensible space systems architecture are presented. These requirements focus on the structure of a given space system. Explicit rationale are given for why the structural system and its conceptual integrity are so important to space-based systems. The triangle-based structural architecture is given as an example of one having conceptual integrity. This discussion emphasizes the important concepts of structural fit, system growth (and shrinkage) potential, and modularity and adaptability.An example of a sensible space systems architecture that satisfies the functional requirements is presented. The design philosophy underpinning this space construction system is highlighted, and it is demonstrated how this system could be used to construct space stations in any configuration studied by NASA during the development of the Space Station Freedom concept. In this context, the importance of architecture vs. configuration is emphasized. Present space systems and those under development are addressed from the perspective of their underlying architectures, or lack thereof. Examples are offered to highlight where and why present architectures are flawed, and why, in many cases, prospects for future growth and adaptability are dubious at best.To demonstrate the versatility of the described space construction system, the design rules and architectural approach used to develop it are applied to other space systems such as launch vehicles, space tugs, human outposts and other space platforms. Examples are given of the system efficiencies obtainable by utilizing these consistent architectural principles throughout the space system infrastructure, thereby enabling consistent and flexible mission architectures.This paper argues for a change in the way humankind is going about its expansion into space and for a change in the way we utilize what is found there. What is needed now in space is a conceptually consistent, flexible and adaptable approach, and not an odd mix of one-of-a-kind, “optimized”, dead-end system designs that consume resources and over-complicate the work at hand.