Rolex Sports Car Series

Following the failure of the United States Road Racing Championship in 1999, the Grand American Road Racing Association announced plans modelled on the USRRC format, centring on the 24 Hours of Daytona. The new series was conceived as an alternative to the IMSA GT Championship, which had been replaced by the American Le Mans Series in 1999. It launched with two classes of Sports Racing Prototypes identical to the rules used in the new FIA Sportscar Championship in Europe, alongside three Grand Touring classes: GTO for larger production-based cars, GTU for smaller production-based cars, and AGT for American tube-frame cars. The league also acquired the Six Hours of Watkins Glen, giving it a second endurance event alongside the Rolex 24 at Daytona to compete with the ALMS's 12 Hours of Sebring and Petit Le Mans. In 2001, GTO and GTU were renamed GTS and GT to better match classes used by the American Le Mans Series.

In 2003 the series introduced a custom prototype chassis known as the Daytona Prototype, named after the series' premiere event. Although Sports Racing Prototypes were permitted through the end of 2003, they were seldom seen as the Daytona Prototypes took over. The American GT class was dissolved in the same year, its cars absorbed into the GTS class. In 2004, the GTS class was abandoned entirely to widen the performance gap between the Daytona Prototypes and GT cars — the GTS cars had proven as fast or faster than the prototypes. The GT class consequently became the top Grand Touring tier and was joined by the Super Grand Sport (SGS) class moved up from the Grand Am Cup series. In 2005, all Grand Touring-style cars were consolidated into a single GT class.

The simplified two-class formula — Daytona Prototypes and GT cars — attracted a large number of competitors, driven by the ease of use and low cost of the cars in both classes, while the Grand American Road Racing Association maintained equalized competition. At shorter tracks where it was not feasible to put 50 cars on track simultaneously, Grand-Am split GT and DP races: GT cars raced on Saturday, DP cars on Sunday. Each race covered the same distance it would have if the two classes ran together.

When GT and DP races were combined, the series used a motorcycle-racing-style "wave start" devised by Roger Edmonson, who had been in motorcycle racing before co-organising the Grand American series with the France family. Daytona Prototypes took the green flag first, followed 20–30 seconds later — depending on track length — by the GT cars, keeping the two classes racing separately for safety.

Due to the series' affiliation with NASCAR, many Sprint Cup Series drivers occasionally participated in Rolex Series races, particularly the 24 Hours of Daytona.

The tire competition began in 2000 with Michelin, Dunlop, Goodyear, Avon, Pirelli, Hoosier, and Yokohama all supplying tires. From 2002 through 2004 the field narrowed to just Dunlop and Goodyear. From 2005 through 2007, Hoosier Racing Tire served as the sole official tire partner. Pirelli succeeded Hoosier from 2008 through 2010, departing for Formula One, the GP2 Asia Series, and GP2 Series following the FIA World Motor Sport Council's Geneva decision on 24 June 2010. Continental then held the tire partner role from 2011 until the series merged into the WeatherTech SportsCar Championship in 2014.

Speed Channel was the near-exclusive broadcaster of the Rolex Sports Car Series, covering the 6 Hours of Watkins Glen and the 24 Hours of Daytona. On 17 August 2013, Fox Sports 1 became the near-exclusive broadcaster for the series until 2014.

On 5 September 2012, Grand-Am announced the Rolex Sports Car Series would merge with the American Le Mans Series to form a unified road racing championship, United SportsCar Racing, later retitled the TUDOR United Sports Car Championship. The final Rolex Sports Car Series race was held on 28 September 2013 at Lime Rock Park.

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