Irrigated agriculture is spreading across the Chihuahuan Desert. Where huge ranches once dominated, farming communities have sprung up and continue to spread despite conservation efforts to halt the advance. Conversion rates and patterns differ across the Mexico-US border, and this comparison provides one lens of analysis for my research. Using extensive in-depth interviews bolstered with textual data, I am tracking the history of land use and conversion across the western corner of the Chihuahua-New Mexico borderland. Mexico’s post-Revolution land reform is one key piece of the puzzle, as are demographic shifts, groundwater regulation, and what is described as recent climate change. I hope that findings will inform land use planning in both countries and forecast the future of Mexico’s ejido system, at least in arid areas.