There was a time when\xa0consumer goods companies paid musicians, athletes, and actors for endorsements,\xa0or\xa0to\xa0license\xa0their name and likeness. But in recent years, there's been an explosion of celebrities getting into business directly, selling everything from shapewear to tequila. Ayelet Israeli, professor at Harvard Business School,\xa0says\xa0the\xa0growth\xa0of social media\xa0and\xa0online,\xa0direct-to-consumer\xa0retail accelerated this trend, but notes that not all celebrity brands are a success. She explains what works and doesn't, and outlines lessons for non-famous\xa0entrepreneurs and established companies.\xa0Israeli is\xa0coauthor of the HBR article\xa0"What Makes a Successful Celebrity Brand?"