Regenerative life support (RLS) systems potentially offer a level of self-sufficiency and a concomitant decrease in logistics and associated costs in support of space exploration and habitation missions. Current state-of-the-art in plant-based, regenerative life support requires resources in excess of resource allocations proposed for candidate mission scenarios. This situation has resulted in plant-based systems being relegated to a supplemental role, supplying only approximately 10% of the food supply. The goal of this paper is to review recent advances in performance in light of likely resource constraints imposed by candidate mission scenarios and determine if it is possible to achieve a level of performance that would make plant-based, RLS feasible. Recent advances in plant-based, RLS supported by the NSF as part of the CELSS Antarctic Analog Project (CAAP), place RLS system at the threshold of system feasibility for candidate space exploration mission scenarios. Control of plant-based, life: support processes, management of mass and energy flow through the crop community, and delivery of nutrients and water to crops sufficiently to satisfy demand with minimum water mass requirements are key to achieving feasibility. Plant-based RLS, as currently practiced by NASA, is not adequate to meet the requirements of future NASA missions. The results of CELSS Antarctic Analog Project provides the basis for achieving feasibility in plant-based. regenerative life support systems.