The Docklands Light Railway (DLR) is an automated light metro system serving the redeveloped Docklands area of London, England. First opened on 31 August 1987, the DLR has been extended multiple times, and now reaches north to Stratford, south to Lewisham, west to Tower Gateway and Bank in the City of London financial district, and east to Beckton, London City Airport and Woolwich Arsenal. Further extensions are under consideration.

Normal operations are automated, so there is minimal staffing on the 149 trains (which have no cabs) and at major interchange stations; the four below-ground stations are staffed, to comply with underground station health and safety regulations.

The DLR is owned by Docklands Light Railway Ltd, part of the London Rail division of Transport for London (TfL). It is operated under a franchise awarded by TfL to KeolisAmey Docklands, a joint venture between transport operator Keolis and infrastructure specialists Amey plc, having been run previously (1997–2014) by Serco Docklands.

Passenger numbers have greatly increased as the network has expanded, and in the financial year 2019/20 there were 116.8 million passenger journeys.