San Joaquin Regional Transit District (known as "San Joaquin RTD" or simply as RTD) is a transit district that provides bus service to the city of Stockton, California and the surrounding communities of Lodi, Ripon, Thornton, French Camp, Lathrop, Manteca, and Tracy.

That same year, RTD introduced low-emission diesel-electric hybrid buses via its “Flower Bus,” with a full-wrap sunflower display designed to complement the slogan “A Breath of Fresh Air.” At the end of 2006, RTD opened the Downtown Transit Center for the public, with a floor for employee offices.

The local agencies that make up the board of the CTSA are: BRT Express is RTD's express bus service and uses uniquely branded, low-emission diesel–electric hybrid buses that arrive at their stops every 15 minutes during weekday peak hours and every 30 minutes on weeknights, weekends, and holidays.

Fare vending machines, located at BRT Express stops and the Downtown Transit Center (DTC), are available for passengers to purchase single ride and all-day passes.

BRT Express uses the same fare structure and passes as RTD’s regular fixed routes and passes issued by the Fare Vending Machines can be used on any of RTD's regular fixed routes that operates within the Stockton Metropolitan Area (SMA).

Completed December 2006, the DTC at 421 E. Weber St. has three off-street bus lanes, two passenger boarding platforms, and a two-story building.