Square
Founded: 2010
Dorsey's mobile-payments company, co-founded with Jim McKelvey, has been transformational for small merchants, enabling them to accept credit cards. Some 3 million businesses use the platform to process about $10 billion in annual payments. Dorsey's out-of-the-box thinking also applies to his management style: At the company's San Francisco headquarters, the 36-year-old CEO can often be found working on his iPad at one of the company's "open collaboration" tables. Dorsey says this allows him to be more accessible to his company's 450-plus employees. (He also leads a weekly neighborhood cleanup project with staff.) But Dorsey's unconventional leadership approach doesn't mean he isn't seeking mainstream success. Last year he struck a deal last year to process all credit and debit transactions at more than 7,000 U.S. Starbucks locations.
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