Since 1967, Butler Ambulance Service has been one of the largest EMS agencies in the United States. Based in Butler, Pa., it is an emergency and nonemergency ambulance transport service provider. The firm offers its sick and injured patients a wide range of related services, such as wheelchair van service. Butler Ambulance Service provides as many as 10 advanced life support ambulances, eight wheelchair vans as well as a paramedic response truck to serve its customers.