Technical Abstract: Because management decisions are made at the farm level, effective conservation practices must be both efficient in controlling air- and water-borne farm emissions and feasible with regard to farm production and profit. The Integrated Farm Systems Model (IFSM) provides a process-based simulation of farm production systems, which enables a comprehensive evaluation of the impacts of changing one or more production practices on net profit, ammonia and greenhouse gas emissions, and water-driven transport of nitrates, sediment, and phosphorous. IFSM is useful in evaluating relative benefits of practices such as precision feed and forage management to reduce incoming nutrients and practices such as manure separation, cover cropping, and forage or pasture management to mitigate off-farm losses of excess nutrients. By using modeling to compare tradeoffs in controlling key pollutants with associated cost-effectiveness, management practices best suited to improving air and water quality of the Chesapeake Bay region can be determined.