The Brihanmumbai Electricity Supply and Transport Undertaking (BEST) is a civic transport and electricity provider public body based in Mumbai, Maharashtra, India. It was originally set up in 1873 as a tramway company called "Bombay Tramway Company Limited". The company set up a captive thermal power station at the Wadi bunder in November 1905 to generate electricity for its trams and positioned it to also supply electricity to the city and re-branded itself to "Bombay Electric Supply & Tramways (BEST)" Company. In 1926, BEST also became an operator of motor buses. In 1947, the BEST became an undertaking of the Municipal Corporation and rebranded itself to "Bombay Electric Supply & Transport (BEST)". In 1995 the organisation was renamed to "Brihanmumbai Electric Supply & Transport (BEST)" alongside Mumbai. It now operates as an autonomous body under the Municipal Corporation.

Water transport in Mumbai consists of ferries, hovercraft and catamarans.