It featured the 1991 FIA Sportscar World Championship, which was contested over an eight race series from 14 April to 28 October 28, 1991.
The series was open to Group C Sportscars, with Category 1 cars complying with new 1991 Group C rules and Category 2 cars running under the pre 1991 regulations.
In order to be classified for points, a team had to complete 90% of the winner's distance.
Further, drivers were required to complete at least 30% of their car's total race distance to qualify for championship points.
[1] Teams only scored points for their highest finishing entry.