Stephanie Agresta, EVP, global director of digital strategy and social media, Porter Novelli, 39

At Porter Novelli, Stephanie Agresta has built a team of social and digital media experts and strategists and driven initiatives for many high-profile clients, including Microsoft, PepsiCo, Hewlett-Packard, and Procter & Gamble. Agresta has also established strategic partnerships with Twestival, Internet Week, and Social Media Week, and was behind the effort that helped the firm win an AOR task for digital activities for Chicago-based Bel Brands USA Inc.'s The Laughing Cow Wedges and Mini Babybel brands. In 2008, she launched ...