Singapore Bus Services (SBS) was a public bus operator in Singapore formed in 1973 from the merger of three private bus companies; the Amalgamated Bus Company, Associated Bus Services and United Bus. The government-sanctioned merger was undertaken to improve service standards of the bus transport system, which formed the backbone of public transport then. The fledgling company was listed on the Stock Exchange of Singapore in 1978 under the name of Singapore Bus Service (1978) Limited.