El Proyecto Arqueologico Lago Suches (PALS) is an interdisciplinary, multi-year project that is investigating the history of land use, the evolution of rural pastoral societies, and the role of Holocene climate changes of the Lake Suches basin of southern Peru.The Lake Suches zone is a high-elevation basin straddling the Departments of Moquegua, Tacna, and Puno, Peru.  The lake is at an elevation of 4600 meters above sea level (masl) and mountain peaks in the basin reach 5200 masl. Our research shows that the area around Lake Suches was occupied early in the Holocene, dating back to approximately 10,000 years ago, and has a nearly continuous occupation into the modern period.  Important changes were shifts from an early, mobile hunter-gather economy that focused on hunting wild camelids to a unique sedentary pastoral mode in the late prehispanic period.  Rural communities appeared and evolved as urbanized cities developed in the Titicaca Basin, reflecting long-distance economic and social ties throughout the urban centers and rural highlands. In this high-elevation environment, rural communities rely on large herds of alpacas and llamas that provide wool, food, and commodities that they can sell/trade to external markets.  The ability to live and herd in the Suches region is contingent on the health of unique, high-elevation wetlands called bofedales that provide pasturage to herds.  In addition, bofedales are important ecological resources for ensuring that water is available year-round in this semi-arid region, as well as to the arid Pacific coast of Peru downstream from the highlands. Palaeoclimate research shows that water resources locally were very stable, in contrast to dramatic fluctuations between periods of drought and wet conditions elsewhere in the Andes, and may have been due, in part, to the careful management of bofedales resources by early herding populations.  Despite significant environmental stability in the Suches basin, profound changes occurred in rural communities as they participated in extra-local economies and reacted to the rise and decline of state societies in the Andean region.