AMR is locally operated in 37 states and the District of Columbia. More than 18,000 AMR paramedics, EMTs and other professionals, with a fleet of 4,200 vehicles, transport nearly four million patients nationwide each year in critical, emergency and non-emergency situations. Outside the urban cores of the largest cities, AMR often has a de facto monopoly in many suburban and rural areas (e.g., Silicon Valley). The colorful and distinctive livery of its vehicles is synonymous in those regions with "ambulance."