Following the obligatory career in Karting, which included finishing runner-up in the Italian Open Masters ICA Junior Championship and winning the 2002 European ICA Junior Championship, Sebastien made the switch to single-seaters in 2004, aged 15, entering the German Formula BMW series.
In his first season, he finished third overall, following this up by finishing runner-up the following year. It's worth noting that in 2004 he was beaten by a certain Sebastian Vettel, while in 2005 it was Nico Hulkenberg who did the business.
For 2006, Sebastien moved up to the Spanish F3 Championship but after just one race he switched to the Formula 3 Euroseries.
With just one win, the Swiss driver could only manage equal-eleventh in the championship standings, though he impressed with a podium finish in the Ultimate Masters of Formula 3 and fourth in Macau.
He remained in the Formula 3 Euro Series for 2007, finishing the season runner up to Romain Grosjean. In addition to this he replaced Michael Ammermuller in eleven rounds of the GP2 Series, contested the Macau GP (he finished 11th) and even found time to represent his country in A1 GP. Then there were also two tests for the Red Bull F1 team.
Sebastien got 2008 off to a great start, not only by being signed as official test and reserve driver for Red Bull, but by finishing runner-up in the inaugural GP2 Asia Series, albeit 24 points behind Romain Grosjean.
In the main GP2 Series, which again he contested with Arden, the Swiss driver finished sixth overall courtesy of Sprint Race wins in France and Hungary.
The new rules meant there was little F1 test action during the course of the season, however, once the World Championship was over, Sebastien was kept busy dividing his time between Red Bull and Toro Rosso.
He constantly topped the timesheets but in all honesty this was more about the fact that his rivals were running in 2009-spec, with less downforce, than anything else.
On January 9, just under two weeks before testing for the 2009 season was due to resume, Toro Rosso announced that Sebastien had been signed, leaving it almost a month before they confirmed Sebastien Bourdais as his teammate.
Little was known about the Swiss youngster, though he certainly appeared fast. Historically, the last Swiss F1 driver was Jean-Denis Deletraz who took part in three Grands Prix in 1994 and 1995 with Larrousse and Pacific. However, in the eyes of many it was how he shaped up to Swiss legends Jo Siffert and Clay Regazzoni that really mattered.
As it happens, despite the shortcomings of the STR4 - and there were many - Sebastien gave a good account of himself.
For the first four races the team used the aero package featured on the original Red Bull launch car and thereafter remained several steps behind its sister team. Furthermore, it was well into the season (Hungary) before the Faenza team got its hands on Red Bull's evolved double diffuser, the Italian team using a 'standard' diffuser for the first few races.
The Italian team was never really able to match the weight distribution of its Milton Keynes counterpart which was to have a direct impact on its aerodynamic performance the car suffering terribly from oversteer. However, to his credit, and unlike teammate Bourdais, Sebastien simply got on with the job doing the best he could under the circumstances.
On his F1 debut (Melbourne) he out-qualified his illustrious teammate and subsequently went on to out-pace him in the race also.
While Bourdais only made it into Q2 on two occasions, Sebastien made it to Q3 in China and in the final three races of the season, by which time the STR4 was finally looking good, he was a regular in the final qualifying shootout.
Finishing in the points on four occasions, Sebastien, though not setting the world alight Vettel-style, gave a good account of himself and it came as no surprise when the Faenza outfit retained him for 2010.
Sadly, two things affected Sebastien in 2010, the obvious progress being made by his teammate, Jaime Alguersuari, and the fact that for the first time Toro Rosso was having to build its own car as opposed to using one of its big sister's cast-offs.
Although nothing special, the STR5 did the job, allowing Sebastien to hone his skills, even though there was an obvious period when, rattled by the threat from his Spanish teammate, the Swiss appeared to suffer a lack of self belief.
Though he regularly made it into Q2, Sebastien often struggled on Sundays. He was the innocent victim of Kamui Kobayashi's wing failure in Australia, while in China he was once again caught up in another driver's problems, this time Tonio Liuzzi.
The first point came in Monaco, while eighth in Canada was followed by a ninth in Britain. However, once Williams and Sauber had come to grips with their own problems the Faenza team was essentially left for dust, ending the season ninth in the Constructors' Championship, the last of the point scoring teams, while Sebastien's eight points left him sixteenth in the drivers' standings.
Retained for 2011, in the early stages of the season, the STR6, though reliable, was neither consistent or particularly pacy. However, as the season developed and the updates began appearing things began to improve.
Sebastien got his season off to the perfect start in Australia where he qualified tenth and brought the car home in eighth, perhaps spurred on not so much by teammate Alguersuari but Daniel Ricciardo who was waiting in the wings. That said, when the pair collided at the start of the race, Helmut Marko was probably already on the phone to Dietrich Mateschitz.
It's fair to say that the Swiss had his share of bad luck, the puncture at Silverstone, the wheel nut problem in Japan, engine in India and hydraulic issue in Abu Dhabi, all conspiring to lose him and his team precious points.
Managing to out-qualify his teammate thirteen times over the course of the year, Sebastien also made some blistering starts, while his overall performance appeared more mature. Certainly his consistency was excellent, none of his five retirements being due to errors of his own making.
Considering the reliability of the teams in 2011, with Red Bull, McLaren, Ferrari and Mercedes regularly bringing their cars home and filling the top eight places, Sebastien did well to score further points in Turkey, Italy and Japan, while his eighth place finish in Hungary - where he started from the back row of the grid - was superb.
As we have seen many time before however, Toro Rosso has history, and consequently it didn't come as too much of a surprise when, on 14 December, the team announced the Swiss had been dropped. The fact that the team dumped both drivers - in favour of Ricciardo and Jean-Eric Vergne - did raise a few eyebrows however. Indeed, it's understood that Sebastien heard the news whilst working on the team's simulator.
On 5 January, with only two seats remaining on the 2012 grid, Red Bull threw Sebastien a lifeline when it confirmed him as its test and reserve driver. That said, the rules meant there was precious little time in the RB8, the Swiss confined mostly to the simulator and demo runs.
Signed to contest the 2012 Le Mans 24 Hours with Toyota Motorsport, driving a TS030 Hybrid with Anthony Davidson and Stephane Sarrazin, after a strong performance, the car was running in third when the Briton collided with a GT Ferrari and crashed heavily.
In 2013, once again retained by Red Bull as test and reserve driver, following Mark Webber's announcement that he was joining Porsche in Sports Cars in 2014, Helmut Marko admitted that Sebastien was not being considered as a replacement for the Australian, the drive eventually going to Daniel Ricciardo. Indeed, the fact that he played no part in the Young Driver Test at Silverstone, for either Red Bull or Toro Rosso, suggests that his racing career in F1 is over... other than simulator work and the obligatory demonstrations.
Nonetheless, alongside his F1 duties - such as they were - he continued with Toyota in the WEC, finishing the season third overall courtesy of a win at the final round (Bahrain), with co-drivers Davidson and Sarrazin, and second at Le Mans.
Retained again by Red Bull for 2014 as test and reserve driver, Sebastien only drove the RB10 once, on the first day of the Barcelona in-season test. Other than demo runs and promotional events his main work for the Austrian team was in the simulator.
Alongside this however, the Swiss continued with his WEC programme with Toyota, winning the title (with Anthony Davidson), courtesy of victories at Silverstone, Spa, Fuji and Shanghai. Sadly he could only manage at Le Mans.
He also found time to contest the new FIA Formula E Championship, partnering Nicolas Prost at e.dams Renault, finishing 2nd overall in the series debut season, with 3 wins from 11 races.
Over the next few years it was pretty much business as usual, with WEC with Toyota, and subsequently Toyota Gazoo, Formula E and test and reserve duties with Red Bull.
Winning the second season of Formula E in 2015/2016, Sebastien finished runner-up in 2016/2017. 2017 also saw him finisher runner-up in the WEC standings.
In 2018 he finally won Le Mans, alongside Kazuki Nakajima and Fernando Alonso, going on to win the WEC title for the second time also.
In mid-January 2019, Red Bull announced that Sebastian had been retained as reserve driver, his ninth year as a member of the Austrian squad, the Swiss, by default, also reserve driver for Toro Rosso.
Alongside his Formula E programme, Sebastien also continued in WEC with Toyota, and while he could 'only' manage second in the all-electric series, he won at Le Mans for the second successive year, while also winning the 2018/2019 WEC title.