Valles caldera is a large, Quaternary silicic volcanic complex that contains a hot, but relatively small, liquiddominated geothermal resource (210o to 300oC; 20 MWe proven). The portion of the caldera having geothermal significance is now part of the recently created Valles Caldera National Preserve. Past development problems, small size, an uncertain power market, and new public status make future development of the Valles geothermal resource uncertain