Grey-Green was a bus and coach operator in England. It was based in Stamford Hill and operated in London and the East of England.

Arriva London is a major bus company operating services in Greater London. It is a subsidiary of Arriva UK Bus and operates services under contract to Transport for London. It was formed in 1998 from a fusion of previously separate Arriva subsidiaries Grey-Green, Leaside Buses, Kentish Bus, London & Country and South London Transport. Operations are split between two registered companies, Arriva London North Limited and Arriva London South Limited.