Cosworth is a high-performance engineering company founded in London in 1958, specialising in engines and electronics for automobile racing (motorsport), mainstream automotive and defence industries. Cosworth is based in Northampton, England, with North American facilities in Torrance, Indianapolis and Mooresville and an Indian facility in Pune.

Cosworth has had a long and distinguished career in Formula One, beginning in 1963. Two Formula One teams were supplied with Cosworth engines in 2006: the Williams team using Cosworth V8 engines, transmissions, and associated electronics; and the Scuderia Toro Rosso team using rev-limited Cosworth V10s based on 2005 spec engines. The end of the 2006 F1 season marked the end of Cosworth's remarkable 43 year association with the series, as no team opted to use Cosworth for 2007. Cosworth returned to Formula One in 2010 as an engine supplier to Williams and three new teams (Hispania Racing F1 Team, Lotus Racing and Virgin Racing), with first units shipped in January. Cosworth's 176 wins make it one of the most successful engine manufacturers to race in F1, second only to Ferrari in victories.