18.) Rob Zangardi & Mariel Haenn
WHY THEY MATTER The stylists behind Hollywood's most glamorous couple, J.Lo and A-Rod, might also be the busiest. Between awards shows, press tours, premieres, TV shows (Lopez's World of Dance and client Heidi Klum's America's Got Talent), Vegas residencies (Lopez's All I Have and client Gwen Stefani's Just a Girl), music videos and tours and ad and editorial shoots, Zangardi estimates that they "pulled together close to 2,000 looks" for clients in the past 12 months. "We also act as the creative directors for all of the Jennifer Lopez brands internationally and Privé Revaux eyewear," he says.