The Volkswagen Transporter (T4), marketed in North America as the Volkswagen Spacebus, is a bus produced by the German manufacturer Volkswagen Commercial Vehicles between 1990 and 2003, succeeding the Volkswagen Type 2 (T3) and superseded by the Volkswagen Transporter (T5).
Introduced in 1990, the T4 was the first Volkswagen van to have a front-mounted, water-cooled engine. Prompted by the success of similar moves with their passenger cars, Volkswagen had toyed in the late 1970s with the idea of replacing their air-cooled, rear-engined T2 vans with a front-engined, water-cooled design. The reasons for deciding in 1980 to instead introduce a new rear-engined T3 are unclear. Thus, the introduction of a front-engined layout was delayed until the arrival of the T4. After a run of nearly 14 years, T4 production ceased in 2003, making it second only to the T1 for length of production in its home market.