Greater Manchester Metrolink Limited (GMML) was a private company formed by the GMA consortium (GEC Alsthom, John Mowlem plc and AMEC) in 1989 to design, build and operate the Metrolink light rail system in Greater Manchester, England. Construction of the Metrolink system began in March 1990.
The contract was awarded for 15 years subject to early termination should the network be extended. In 1997 contracts for extension were let to Altram (Manchester), a consortium of Ansaldo Transporti, Serco Investments Limited, Laing Civil Engineering and 3i. Serco Metrolink, a wholly owned subsidiary of Serco Limited, took over the operations and maintenance of the system on 26 May 1997. In March 2003, Serco Investments bought out its partners and Altram (Manchester) Limited became a wholly owned subsidiary of Serco.
In July 2007 the contract to operate Metrolink was awarded to Stagecoach Metrolink, a subsidiary of the Scottish transport company, Stagecoach Group plc. Unlike Serco, Stagecoach do not own the concession, merely operate it on a fixed-term management contract.