Sir Martin Stuart Sorrell is a British businessman and the founder of WPP plc, the world's largest advertising and PR group, both by revenue and the number of staff. Upon his retirement in April 2018, Sorrell was the longest-serving chief executive of a FTSE 100 company. He is also known for being consistently one of the UK's highest-paid corporate executives. Sorrell has served on boards and advisory bodies of a number of high-profile public, academic and business organisations, including several leading business schools, both in the UK and internationally.