How a New Orleans native turned around a cruise company sinking from a public relations disaster... to one of the most valuable brands in its industry. When Arnold Donald took over Carnival Corporation and the nine cruise lines it operates, one of the biggest things he did was build a new leadership team. Seven of the cruise lines got new heads, including more women and minorities. He says that "diversity of thinking is a business imperative and a powerful advantage," and that you get better ideas and new growth opportunities when your leadership is diverse.