Consistent constraints on what can be built for space have existed throughout the life of the space program. Limits have been placed on size, weight, and structural durability (due to launch) of every craft or piece of equipment that has been sent into orbit. Additionally, extended missions require that replacement parts must either be stockpiled or sent up from earth, causing a substantial time delay. If, instead, equipment and spacecraft could be manufactured in the zero gravity environment of space, these constraints could be overcome. This would enable the creation of structures of nearly limitless size and intricacy that could not be launched, and in some cases could never be manufactured on earth. Extended missions could reduce weight in spare parts and overcome the dependency on earth. Current 3D printing technologies can provide a platform for this type of fundamental shift in space manufacturing.