An innovative microwave system is proposed for the continuous production of medical grade water. This system will utilize direct absorption of microwave radiation to rapidly heat potable water well above normal autoclave conditions, achieving equivalent microbial lethality in much shorter times. High thermal efficiencies will be gained by placement of the microwave antennae directly in the flowing water stream allowing very efficient volumetric coupling of microwaves. The sterilized water stream will then pass through a regenerable endotoxin filter to achieve water for injection (WFI) purity standards. This filter will remove endotoxins by selective adsorption. The combined system will enable the energy efficient and practical production of WFI aboard spacecraft or planetary habitats under microgravity or hypogravity conditions with a low equivalent system mass (ESM). In the Phase I research, sterilization chambers and endotoxin filters will be designed, assembled, and tested. The Phase II program will deliver a fully instrumented, computer-controlled system with a low ESM whose performance is well documented. This technology will form the basis for multiple applications in commercial sterilization markets.