The Docklands Light Railway is a driverless computer controlled light rail system linking Canary Wharf and the Isle of Dogs to the City of London to the west, Stratford to the north and Beckton to the east.

In 1996 CGL Rail Link plc won the concession to design, build, finance and maintain an extension to the system, from the southern end of the Isle of Dogs under the Thames to Lewisham. The extension provides improved public transport links between east and south-east London, the City and the new employment opportunities in the docklands area, helping to sustain its regeneration.

Construction of the 4.2km extension scheme of which approximately 1.65km is underground, comprised twin bore tunnels beneath the Thames, an 830m viaduct, four overground stations and two new underground stations.

Construction and commissioning was completed ahead of schedule and the extension opened on 20 November 1999, two months earlier than the contracted date. The concession contract provides for the concessionaire to be paid availability fees when the railway is available for DLR (through its franchise agreement) to operate trains. A variable usage fee will also be paid on a share of the ticket revenue from 2009.

Working closely with DLR, from its base of operations in Greenwich, CGL Rail employs a team of 25 staff who ensure that the extension operates as a safe and well maintained section of railway infrastructure, so that DLR and its network operator can provide a reliable service to commuters and visitors to Greenwich and the East of London.

Construction and commissioning was completed ahead of schedule and the extension opened on 20 November 1999, two months earlier than the contracted date.