POLARIS personnel have been key members of design, preparation, and control teams for a number of spill response exercises. These teams are responsible for formulating the Exercise Plan through a series of established exercise objectives. Preparation for exercises entails development of scenarios, formulation of evaluation guidelines and forms, and scripting of exercise inputs. Generally, key members of the exercise design team participate in the exercise in one or more capacities: controller, facilitator, coach, evaluator, or participant. POLARIS staff has participated in numerous drills representing responsible parties and have facilitated with bi-national Mexico-US (MEXUS) and Spills of National Significance (SONS) exercises.