[citation needed] SPT has the following main responsibilities:[citation needed] Until 1986 SPT (and the Greater Glasgow Passenger Transport Executive before it) was directly responsible for running the municipal bus services in Glasgow, and owned both the buses and the necessary supporting infrastructure.

[4] The Greater Glasgow Passenger Transport Executive (GGPTE), the forerunner of SPTE, started operations in 1973, taking over the entire municipal owned and operated bus, and Underground railway, services of Glasgow Corporation Transport (GCT), which had been in existence from 1894 to 1973.

The new livery had Verona green on the lower panels, and yellow between decks, white was used for window surrounds, and the roof.

The orange and black colour scheme used later on in the 1980s to 1990s was originally a special livery for a small fleet of cut down single deck Leyland Atlanteans that operated the Glasgow Central to Queen Street rail link service.

[citation needed] As GCT had done, the GGPTE continued to buy large numbers of Leyland Atlantean double-decker buses, they were by far the most numerous type of bus in service, but GGPTE also introduced new bus types such as the Scania-MCW Metropolitan, and the front-engined, Scottish-built, Volvo Ailsa.

Gradually the "GG" logo was discontinued, and "Trans-Clyde" was used alone although a Volvo Citybus prototype was branded in the same livery with "Strathclyde" instead.

Bus stop pennants were given "Strathclyde Transport" branding by having a sticker placed on top of the old "Trans-Clyde" name.

The name lasted until 1986 due to deregulation of the bus industry, The orange and black colour scheme was kept and "Strathclyde's Buses" branding was used.

At that time SPTE acquired Buchanan Bus Station from Scottish Citylink which led to a substantial refurbishment completed in 1995.

Opened in 1896, it is the third-oldest system of its type in the world, and the only one that has never been expanded from its original route[citation needed].

However it was later decided to revamp the subway over a long term programme which includes a refurbishment of all the stations, new escalators, improved disabled access, new ticketing system and later on driverless signals and trains.

Between 1972 and 2002, SPT and its predecessors were actively involved in the operation of suburban railways in the Greater Glasgow area.

Some trains from 1975 to 1979 were also being painted in BR's new livery of white, with a blue stripe, with the addition of the GG logo.

From 1980 the trains were repainted in British Rail Blue/Grey livery; again the GG logo was used with the addition of "Trans-Clyde" branding.

From 1983, due to SPTE's rebranding, the BR logo was now used along with "Strathclyde Transport" branding on the centre of each car, following repaints.

[citation needed] In August 2008 the Scottish Government's agency Transport Scotland announced that all ScotRail trains (including former SPT services) would be repainted in Transport Scotland blue livery with white Saltire markings on the carriage ends, and SPT Rail branding and the carmine and cream livery were removed.

[8] SPT operated the Renfrew Ferry until March 2010, when Silvers Marine took over the service trading as Clyde Link.