The 250 GTO was designed to compete in Group 3 GT racing, where its rivals would include the Shelby Cobra, Jaguar E-Type and Aston Martin DP214. The development of the 250 GTO was headed by chief engineer Giotto Bizzarrini. Although Bizzarrini is usually credited as the designer of the 250 GTO, he and most other Ferrari engineers were fired in 1962 due to a dispute with Enzo Ferrari. Further development of the 250 GTO was overseen by new engineer Mauro Forghieri, who worked with Scaglietti to continue development of the body. The design of the car was a collaborative effort and cannot be ascribed to a single person.