South West Trains (SWT) is a British train operating company owned by Stagecoach Group operating the South Western franchise.
It operates the majority of commuter services from its Central London terminus at London Waterloo to South West London as well as most outer suburban/regional services in Surrey, Hampshire and Dorset. It also provides regional services in Devon, Somerset, Berkshire, and Wiltshire and on the Isle of Wight. The area of operation, essentially the former South Western division of Network SouthEast, is also roughly that of the pre-1923 London and South Western Railway (excluding everything west of Exeter). The Stagecoach Group took over the franchise on the privatisation of British Rail in 1996 and retained it in 2004 and again in 2007 making it, along with Chiltern Railways, Virgin Trains and First Great Western, the longest-running franchise. It is a particularly complex operation due to the large number and variety of services.