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Stewards of western rangelands manage increasingly complex social-ecological systems with few decision-making tools to assist them. Our integrated research team has developed a linked ecological and economic state-and-transition model (STM) to help ranchers and land managers understand the effects of economic decisions on land health and ecosystem services, including the impacts of changing ecological conditions on ranch economic viability and profitability. Our model is parameterized for the Elkhead Watershed in Northern Colorado. The STM model was developed using both field collection and local knowledge as inputs. The STM model consists of three distinct ecological sites (Claypan, Mountain Loam, and Aspen), in addition to riparian habitat, hay production and pastures. Production estimates were determined for all potential states of the three ecological sites. States and transition probabilities were incorporated into a Stochastic Dynamic Programming (SDP) model which was developed to determine the optimal cattle management decisions in order to maximize an infinite stream of returns to a “representative” ranch in the watershed (representing the overall mix of ecological sites as observed across the watershed). Management options include stocking decisions, spraying of each ecological state, and haying operations while stochastic variables include random precipitation and fire events. The model was also run for scenarios that aim to maximize the various ecosystem services (including wildlife habitat for grouse, elk or deer, as well as overall plant diversity and soil erosion potential). Results show that both current ecological states and economic conditions impact optimal behavior. Results also show that management decisions are altered when accounting for ecological state impacts on ecosystem values, and the costs of conserving such ecosystem services (preventing transitions) is far less than the costs of restoration (reversing undesirable transitions).