In 1975, Waley-Cohen married The Honourable Felicity Ann Samuel, daughter of Marcus Samuel, 3rd Viscount Bearsted.[2] The couple have four children, Marcus, Jessica, Sam and Thomas. Thomas died in 2004 from cancer.[3][4]
He has three siblings. His brother is Sir Stephen Waley-Cohen a senior figure in the world of theatre, and operator of St Martin's Theatre home of The Mousetrap. He has two sisters, Rosalind, who is married to the former New Zealand politician Philip Burdon and Joanna a professor at New York University. His nephew, Jack, is the question editor for BBC quiz Only Connect and founder of What3words.
Waley-Cohen started his career in 1969 with Christie's auction house, where he remained until 1981.[8] He has founded multiple companies including a founding shareholder and director of Portman Healthcare, a dental business, founder and CEO of Alliance Medical and later founder and CEO of Alliance Imaging Inc in California. Waley-Cohen is on the board of American investment company Brown Advisory.[9]