The theme of this symposium will be integration of active optical sensors into an adaptive management program to create site-specific nitrogen recommendations. The goal of the symposium is to provide the latest information on the benefits and pitfalls of sensor-based nitrogen management. The symposium will provide a mix of presentations about the technical underpinnings of sensor-based and adaptive management approaches to nitrogen management. Efforts to achieve production goals, water quality benefits, and improved global nutrient use efficiency will be shown. Perspectives from the U.S., Europe, and Mexico will be provided.