*By Conor White* There are only three black chief executives of Fortune 500 companies, and that has to change, according to a CEO who knows something about breaking down racial barriers to the C-suite. As CEO of Carnival Corporation, the largest cruise line in the world, Arnold Donald says that diversity is a valuable business strategy. "For our communities to thrive, for our companies to thrive, we have to proactively engineer diversity of thinking into our companies," Donald said in an interview Thursday with Cheddar. "That's what I'm doing at Carnival, that's what I've done at other places, and the results speak for themselves." In Donald's five years as chief executive of Carnival, its market cap has increase from $27 billion to $45 billion. Despite living in the age of data gathering, machine learning, and social-media influencers, Donald said he still believes in Carnival's old-fashioned appeal. "The most powerful marketing tool is word of mouth," he said. "We have a lot of people who cruise, as I mentioned 83 million passenger cruise days a year, nearly 13 million guests just on our ships, and if you know someone who went on a cruise, and you trust them, they're your most reliable resource." For the full interview, [click here](https://cheddar.com/videos/carnival-corporation-ceo-talks-record-setting-year).
