Rob Reilly, Global Creative Chairman, McCann Worldgroup

In an industry with no shortage of Negative Nancies, Rob Reilly is a perpetual, evangelical optimist. But he wasn't always: He once had an employer require him to take a year's worth of classes to learn how to be more respectful of others. Reilly credits that work—among other things—with why he's having such a good run now: The Global Creative Chairman for McCann Worldgroup since 2014, Reilly and his team picked up network of the year for the first time in the agency's history.