Societatea de Transport București is one of the main public transit operators in Bucharest, Romania, owned by the Municipality of Bucharest. From 1990 to 2018, the company had a different legal status and was known as the Regia Autonomă de Transport București (RATB).

The Bucharest Metro is an underground rapid transit system that serves Bucharest, the capital of Romania. It first opened for service on 16 November 1979. The network is run by Metrorex. One of two parts of the larger Bucharest public transport network, Metrorex has an average of approximately 720,000 passenger trips per weekday, compared to the 1,180,000 daily riders on Bucharest's STB transit system. In total, the Metrorex system is 79.1 kilometres (49.2 mi) long and has 64 stations.