created with full support of NASCAR's France family and other motorsports notables and had its inaugural season in 2000. Grand-Am struggled early on, but proved to be a formidable competitor to the ALMS in later years with a different philosophy based on lower-tech cars, most notably its prototype category Daytona Prototype, giving larger fields and closer competition. Much like the split between Champ Car and the IRL, this split was seen by many as being detrimental to the sport as a whole. Purchase by NASCAR and reunification In 2012, Don Panoz sold the Braselton, Georgia-based ALMS to Grand-Am Road Racing, in turn owned directly by NASCAR and helped organize a merger between the ALMS and the Rolex Sports Car Series. In 2013 the unified series was announced as the Tudor United SportsCar Championship (now IMSA SportsCar Championship). The announcement also confirmed that IMSA will manage and sanction the new series, operating as a wholly owned subsidiary of NASCAR. On September 19, 2019, Scott Atherton announced retirement from his position as the President of the International Motor Sports Association at the end of 2019. He had held that role since the merger of IMSA's American Le Mans Series with the Grand-Am Rolex Sports Car Series in 2014. One month following that announcement, then-director of Mazda's motorsports program in North America, John Doonan, was confirmed to be Atherton's replacement. At the 2021 Daytona 24 Hours, IMSA and the ACO announced the historic alignment of the technical regulations for sportscar racing, which was further detailed in June of that year, which brought about the convergence of all sportscar regulations between the FIA, IMSA and the ACO. In January 2022, IMSA bought Historic Sportscar Racing, whose events include the Classic 24 Hours of Daytona, the Classic 12 Hours of Sebring and the Rolex Monterey Motorsports Reunion. Circuits Current sanctioned series These are the series that are currently sanctioned and managed by the IMSA organization. IMSA WeatherTech SportsCar Championship The WeatherTech SportsCar Championship was created in 2014 through the merger of Grand-Am Road Racing and the American Le Mans Series. It debuted under the name Tudor United SportsCar Championship on January 25–26, 2014 at Daytona International Speedway. For the 2016 season title sponsorship changed from Tudor to WeatherTech. This series features Daytona Prototype International, LMP2, LMP3, GTE, and GT3 cars. IMSA Michelin Pilot Challenge The IMSA Michelin Pilot Challenge is a grand touring and touring