Four regenerative ECLSS assemblies, built by Hamilton Standard, have been undergoing testing at NASA's Marshall Space Flight Center (MSFC) during the past year. This paper describes each pre-prototype assembly and presents test objectives and data accumulated over the period of July 1987 through June 1988. The primary test activity was NASA's Integrated Systems Metabolic Control Test conducted in MSFC's Core Module Integration Facility (CMIF). This paper describes the operation and performance of the TIMES urine reclamation assembly and the Sabatier CO2 reduction assembly in that test. The other two technologies covered are the bench testing of the SAWD CO2 removal assembly and the integrated propulsion testing of the Static Feed SPE® O2 generation assembly.