Foulston is the former owner of the Brands Hatch motor racing circuit. Her father John, who founded the Atlantic Computers leasing operation, was killed in 1987 while testing a racing car, his great passion.

He also owned circuits, including Brands Hatch. A year after his death, the sale of Atlantic netted £29m for his family trusts. His daughter took over running the racing circuits and led a management buyout of the business in 1995 for £15.5m.

Four years later the Brands Hatch Leisure business was sold for £120m, netting Foulston, 43, £35m. She then left for Switzerland, where she leads a quiet, low-key life.