Ken MacKenzie has a high-quality problem. How do you follow eight years as chairman of Australia’s most iconic company?

MacKenzie, who officially retired as BHP chairman on Monday, has no shortage of things to keep him busy. There are advisory roles at US private equity firm American Securities Capital Partners and local investment bank Barrenjoey. There’s his role as chairman of the Melbourne Business School, where he’s been a driving force behind the development of the secretive school for ASX chief executives. There are hobbies including skiing, sailing and classic cars. And most important of all, there are four grandchildren.