"Emmo" began as a mechanic before trying motorbikes and finally moving on to racing karts and Formula Vees built by the company set up with his brother. In his second season in single-seaters, Fittipaldi won the Brazilian Formula Vee title at 21 years old. He left for Europe in 1969, with the ambition to convince team owners of his talent in three months. After some podiums and his first victories in Formula Ford, Emerson was engaged by the Jim Russell Driving School Formula Three team. He continued to win, drawing the attention of Colin Chapman, who was looking for a driver to support the Austrian Jochen Rindt in the 1970 Formula One season. The team's No 3 driver, he ended up becoming No 1 driver after Rindt was killed at Monza and John Miles left the team. Thrust into the spotlight by leading F1's top team, he proved up to the task and won for Lotus in its first race post-Rindt.

In his first full year as Lotus' lead driver in 1971, Fittipaldi finished sixth in the drivers' championship as the team experimented with a new chassis, the Lotus 72. Armed with what was arguably the greatest Formula one design of all time, the Lotus 72D Emmo proved unstoppable in 1972 as he won five of 11 races and easily won the F1 Drivers' Championship from Jackie Stewart by 16 points. At 25 he was then the youngest champion in F1 history (his record was eventually topped by 24 year-old Fernando Alonso). It appeared he might do it again in 1973. But after three wins from four attempts with the 72D, he began to struggle in the new 72E that was unveiled mid-year. It resulted in the reverse of the previous year, Stewart beating Emerson for the Drivers Championship by 16 points; though the combination of the 72D and E's points earnings were enough to gain Team Lotus the 1973 F1 Manufacturers Championship.

Fittipaldi left Lotus to sign with the promising McLaren team. Driving the highly efficient McLaren M23, he had three victories in 1974, reached the podium four other times, and beat out Clay Regazzoni in a close battle for his second championship. The following season, he notched two more victories and four other podiums, but was second to a dominant Niki Lauda. However, at the height of his F1 success, Fittipaldi shocked everyone by leaving McLaren to race for older brother Wilson Fittipaldi's Copersucar-sponsored Fittipaldi team.

It was hardly a world class organization and the double champion regularly struggled, even failing to qualify for three races in his time there. Despite this, he remained with the team for five seasons but only managed a best finish of second. Emerson Fittipaldi decided to retire from racing at the end of 1980. He has since said that his last two years in Formula One were very unhappy: "I was too involved in the problems of trying to make the team work, and I neglected my marriage and my personal life", although at the time he cited the deaths of many of his colleagues as his reason. He was only 33, but had been racing in Formula One for a decade. He had failed to finish seven of the last ten races that year and had several times been outpaced by his Finnish teammate. He moved into the management of the team alongside his brother. The team struggled on for another two years with minimal sponsorship, going into receivership at the end of 1982.