The Suburban Mobility Authority for Regional Transportation (SMART) is the public transit operator serving suburban Metro Detroit. It partners with the Detroit Department of Transportation. Beginning operations in 1967 as the Southeastern Michigan Transportation Authority (SEMTA), it operates 44 linehaul and three park-and-ride bus routes in Wayne, Oakland and Macomb Counties. Its name was changed to SMART in 1989. As of 2008, SMART has the third highest ridership of Michigan's transit systems, surpassed by Capital Area Transportation Authority and Detroit Department of Transportation. SMART has its headquarters in the Buhl Building in Downtown Detroit.