A Suit Water Membrane Evaporator (SWME) system was designed at JSC, NASA, for the Advanced Space Suit Portable Life Support System (PLSS). The SWME was investigated to provide a more robust and reliable method of heat transfer for PLSS heat load, providing an alternate technology to the current Shuttle EMU sublimator. The SWME is less sensitive to water contamination, provides gas venting capability to the PLSS thermal loop, and permits control of heat transfer rate via back pressure regulation.The tests served as a technology demonstration of SWME performance in a concentric, dual-sided design configuration, back pressure regulation under water vapor condition, and combined system compatibility. The tests provided preliminary data to characterize SWME performance and investigate the viability of backpressure regulation control. Future investigation will be to test the integrated SWME and electrically controlled backpressure regulator so as to define the SWME performance with respect to backpressure regulation from Automatic Thermal Control perspective.