In motorsport, a privateer is usually an entrant into a racing event that is not directly supported by an automobile or motorcycle manufacturer.
Increasingly, the term is being used in a Formula One context to refer to teams, such as Williams, that are not at least part-owned by large corporations.
Many privateer entrants compete for the enjoyment of the sport, and are not paid to be racing drivers.
From the inaugural 1950 season until 1981, several privateer teams entered chassis at Formula One Grands Prix.
At the 1981 Spanish Grand Prix, Equipe Banco Occidental became the last privateer team to enter Formula One, using a Williams chassis.