Citizenship: Italy Net worth: $2.9 billion
Together with siblings Luciano, Carlo and Gilberto, also billionaires, Giuliana formed Benetton Group in 1965. The $2.5 billion (sales) clothing company sells its United Colors of Benetton, Sisley, Playlife and Killer Loop brands at more than 5,000 stores in 120 countries. She is also a director of Edizione, the family holding company that owns stakes in Atlantia, formerly Autostrade, one of the world's largest toll road companies, and in Autogrill restaurants, which serve nearly 900 million customers each year on highways and in airports in 42 countries. Giuliana started the family's fashion business, knitting sweaters that brother Luciano would then peddle by bicycle. Originally sold under the Tres Jolie label, it was eventually renamed Benetton.