The key to human expansion into space and space development, in general, is developing space activities that deliver value in an economic sense. In other words, the key to space development is making money in space, that is, profit. However, the search for money making space activities has proven elusive. We present a business case for a commercial company to mine lunar ice and process the ice into rocket propellant. We discuss the existing and future markets for propellant and an architecture for mining and processing propellant and the associated costs. We then examine 3 scenarios, 1 commercial stand-alone and 2 involving a public/private partnership (PPP) model with NASA. We provide a comparison with other similar analyses. Business returns are positive for all 3 scenarios, although the PPP models provide increased returns and share risk with the government. Once established, lunar-sourced propellant will dramatically reduce the cost of all beyond low Earth orbit space activities and potentially enable other profitable commercial ventures to emerge.