The 41-year-old is the eldest son of the late Rafik Hariri and the second Hariri to make it into our Rich List. He manages his real estate and private banking business from Geneva. His Horizon Development is planning a $5bn mini-city in the Jordanian port of Aqaba on the Red Sea.
In March 2008, Bahaa left family-owned Saudi Oger, a construction, utility and telecommunications company, to run his own property business. The Boston University graduate is also involved in a $300bn development in northwestern Saudi Arabian city of Tabouk, and according to Forbes magazine, chairs two soccer clubs in Lebanon.