Valentino Rossi (; Italian: [valenˈtiːno ˈrossi]; born 16 February 1979) is an Italian professional motorcycle road racer and multiple MotoGP World Champion. He is the only rider in the history of the World Championship to have won the World Championship in four different classes: 125cc (1), 250cc (1), 500cc (1) and MotoGP (6).
Rossi is one of the most successful motorcycle racers of all time, with nine Grand Prix World Championships to his name – seven of which are in the premier class.
After graduating to the premier class in 2000, Rossi won the 500cc World Championship with Honda in 2001, the MotoGP World Championships (also with Honda) in 2002 and 2003 and continued his streak of back-to-back championships by winning the 2004 and 2005 titles after leaving Honda to join Yamaha. All of those titles were won in a dominant manner, being decided before the final round on all occasions. He lost the 2006 title with a crash in the final round at Valencia, ceding the title to his former Honda teammate Nicky Hayden. In 2007 Rossi and Yamaha were of no match to a dominant Casey Stoner on a Ducati, and Rossi ultimately finished a then career-low third overall.
Rossi regained the title in 2008 following several tight duels with title defendant Stoner and retained it in 2009. After a 2010 marred by a broken leg and no title challenge, Rossi left Yamaha to join Ducati for the 2011 season. Rossi replaced Stoner at Ducati, who went on to win the 2011 title with Honda instead while Rossi endured a difficult spell with his compatriot marque. It was confirmed in 2012 that he would rejoin Yamaha for the 2013 and 2014 seasons after Rossi suffered two winless seasons while at Ducati.
Following his return to Yamaha he has finished second overall in 2014, 2015 and 2016. Rossi led the championship for the vast majority of the 2015 season before being surpassed by team colleague Jorge Lorenzo in the final round at Valencia, with Rossi losing out as a result of a grid penalty sustained for a controversial clash with Honda rider Marc Márquez in the previous Malaysian round. During Rossi's second stint at Yamaha, Márquez won multiple titles in succession with Rossi often having to settle for podium finishes and only occasional wins.
Rossi is currently contracted to race until the end of the 2020 season, when he will be 41 years old. He is also a team owner of junior class team Sky Racing Team by VR46 that competes in Moto2 and Moto3.
Rossi has a maternal half-brother, Luca Marini, who is currently racing in the 2019 Moto2 season for the Sky Racing Team by VR46.