This Edinburgh-born Scotsman with Italian roots took up karting at the age of nine, secured various national titles and moved to the British Formula Vauxhall Junior in 1991. Two years later, he won the regular Formula Vauxhall, which was rewarded with the British Club Driver of the Year award. In 1994, he completed his first full year in the British Formula 3 Championship and finished fourth in the final standings.
The following year, he was already driving a C-Class DTM for AMG-Mercedes in the first combined DTM/ITC season, showed no problems getting used to the new car and was a lively competitor at the front of the field. After three second, one third and one fourth place as his best results, Franchitti placed fifth in the overall DTM standings and even third in the overall ITC standings, with one victory, two second and one third place as top results. In the following year, the first and last ITC-only season, the Scot again put in an excellent performance in the AMG-Mercedes C-Class DTM, finishing fourth overall after a race win in Suzuka, Japan, and seven further podium finishes.
After the two DTM and ITC years, he returned to formula racing and ventured across the Atlantic into the North American CART World Series in 1997. With Team Hogan Racing, he drove a Reynard 97i with a Mercedes-Benz engine from Ilmor and finished his rookie season in 22nd position. The best result was a ninth place in the race on the street circuit in Surfers Paradise, Australia. Franchitti subsequently established himself with various teams as an absolute top driver in CART and, above all, later in the IndyCar series. Highlights of his career in IndyCar include the championship titles in 2007 – including a victory in the Indianapolis 500-mile race – and 2009 to 2011.
Short detours into the NASCAR series and prototype and GT racing did not prevent Franchitti from remaining loyal to the IndyCar Series until 2013. After a serious accident in the penultimate race of the season, however, the Scot ended his active career on the advice of his doctors.