He would have some exposure to motor racing through racing karts and competing in rallies. He would soon realise that he would not be a success as a driver. In the early 1970's Head worked for Lola Cars alongside John Barnard. He was involved in projects relating to cars from Indy, Can Am and two litre sports cars. Head was to move on to working with Ron Tauranac, founder of the Ralt car concern, at Trojan. He assisted in the designing of both Formula 5000 and Formula One cars.

Patrick teamed up with Frank Williams in 1975. After a season with Walter Wolf Racing, the duo set up Williams Grand Prix Engineering in March 1977 and competed with a second hand March.

The first Patrick Head designed Formula One car, the FW06, appeared in 1978. A year later his designs were winning Grands Prix and two years after that, won both the Driver and Constructor World Championships for the first time.