Emergency medical service in the Tre Valli region, canton of Ticino, in southern Switzerland, accredited by the Inter-Association of Rescue. TVS serves a population of 25,000 inhabitants in a rural and mountainous area of 960 km2. We respond to more than 2,000 requests for intervention per year. 15% of the activity consists in medical transfer of patients to specialist hospitals in the center and south of the canton of Tessin. Our main collaborators are paramedics, ambulance technicians and specialist nurses. A component of voluntary supports the activities of our professionals.