In the American entertainment industry, the studio zone, also known as the thirty-mile zone (TMZ) is the area marked roughly around a 30-mile (50 km) radius from the intersection of West Beverly Boulevard and North La Cienega Boulevard in Los Angeles, California, which at one time was the location of the headquarters of the Alliance of Motion Picture and Television Producers (AMPTP), the negotiating body for most studio management. This area includes almost all of the southern half of Los Angeles County, as well as slices of eastern Ventura County and northwestern Orange County.