Apart from Lucian Freud (for whom he is the exclusive worldwide dealer), William Acquavella is better known as a dealer in modern art than that of the contemporary variety (hence his drop down this list). Still, the world’s most expensive living artist isn’t a bad one to have in your back pocket (Acquavella sold Freud’s Girl in Attic Doorway, 1995, for $12 million at this year’s Art Basel), and it’s no bad thing to be the favoured dealer of Steves Wynn and Cohen.