Since retiring from the tour, Cahill has been a successful tennis coach, working with high-profile players such as Lleyton Hewitt, Andre Agassi, Fernando Verdasco, and Daniela Hantuchová.
Since retiring from the tour, Cahill has been a successful tennis coach and guided Lleyton Hewitt to youngest ever player ranked World No.1. Cahill thereafter worked with high-profile players Fernando Verdasco, and Daniela Hantuchová.