Future manned space exploration missions will require space suits with capabilities beyond the current state of the art. Portable Life Support Systems for these future space suits face daunting challenges, since they must maintain healthy and comfortable conditions inside the suit for long-duration missions while minimizing weight and water venting. We propose to develop an innovative, multipurpose garment for thermal and humidity control inside a space suit pressure garment that is simple, rugged, compact, and lightweight. Our approach is to make simple modifications to a conventional liquid cooling and ventilation garment (LCVG) so that it can directly absorb latent heat as well as sensible heat. This hybrid garment will prevent buildup of condensation inside the pressure garment, prevent loss of water by absorption in regenerable CO2 removal beds, and conserve water through use of Creare's lithium chloride absorber/radiator (LCAR) technology for nonventing heat rejection. In Phase I we will prove the feasibility of our approach by sizing the critical components for the hybrid garment, developing fabrication methods, building and testing a proof-of-concept system, and demonstrating by test that its performance is suitable for use in space suit life support systems. In Phase II we will optimize the overall design for integration with space suit systems, produce a full-size prototype garment, and demonstrate operation in a prototypical environment.