Born in Aigle, Switzerland on 31 October 1988, Sébastien Olivier Buemi started his racing career in 2004 competing in the ADAC BMW series, finishing third in the standings in his inaugural season. In 2005, Buemi once again competed in the ADAC BMW series, this time winning seven races and ending the season in second place. In 2006 he competed in the F3 Euroseries finishing 12th in the championship for that season. In 2007 he remained in the F3 Euroseries, finishing the season in second place. During this year Buemi also competed in five GP2 events as a stand-in for an injured team-mate.
Buemi tested for Red Bull Racing F1 in September 2007 in Jerez and clocked in as third quickest on the day, resulting in him being signed as reserve driver for the team for 2008. His performance alongside other world-class drivers put him behind Timo Glock and Vitantonio Liuzzi, and ahead of more experienced drivers such as Rubens Barrichello and Nelson Piquet Jr. On 9 January 2009, Red Bull Racing’s sister-team Scuderia Toro Rosso confirmed that Buema had been signed by the team as one of its drivers for the 2009 season.
Buemi’s first race for Toro Rosso was the 2009 Australian Grand Prix, where he proceeded to pass his team-mate Sebastien Bourdais and finish eighth, thereby scoring a point. With Lewis Hamilton being disqualified from the race, Sébastien Buemi was later moved up to seventh place. Additional points were earned by Buemi at the Chinese Grand Prix, the Brazilian Grand Prix, and the end of season event in Abu Dhabi. It was confirmed in November 2009 that Buemi would compete as part of Toro Rosso for 2010 as his second season with the team.