MICHAEL RUBIN is not ashamed to admit his passion for business— even in the middle of discussing what a perfect day away from the office might entail.

“I love working,” says the 38-yearold president, chairman and CEO of GSI Commerce, after taking a second to consider such a dreamy proposition. Comfortably dressed in a white button-down shirt and black dress pants, Rubin looks entirely at ease behind his corner desk in a corner office of GSI’s King of Prussia headquarters. Save for a BlackBerry tucked into its charger and a can of Diet Coke next to his PC monitor, Rubin’s desk is neat to the point of being sparse. “I feel very blessed and fortunate for that.”

You might imagine a similar scene plays out—a few moments to ruminate over a question, followed by a decisive answer—when Rubin is hashing out headline-making deals for his global e-commerce and interactive marketing services firm. In 2009 the company earned $1 billion in annual net revenues. Not bad for a kid who got his start selling stationery door to door.

At 12 years old, Rubin, an avid skier, converted his parents’ basement into a ski-tuning shop, which later morphed into a consignment business for leftover merchandise and grossed thousands in its first year. By high school, when most teens are just clocking in at their first parttime jobs, Rubin already owned a small chain of suburban ski stores. But the seasonality of his enterprise—“If it doesn’t snow, it’s not good for business,” laughs Rubin—quickly settled in, followed by mounting debt.

It wasn’t until after high school (Rubin attended just one semester at Villanova University) that he broadened the scope of his business plan to sporting goods—particularly athletic footwear—while sticking to his tried-and-true excess-inventory model. In 1999 Rubin “reinvented” GSI, then known as Global Sports Inc., as an e-commerce brand. Today it serves more than 500 of the nation’s leading brands, such as Ralph Lauren, Kate Spade, Godiva, Elizabeth Arden, FAO Schwarz, Nautica and the NFL, by offering what Rubin describes as three separate business segments: e-commerce solutions, marketing services and consumer engagement.

With more then 5,500 employees worldwide—the majority of whom are based in the US—Rubin, who, with wife Meegan, has a four-year-old daughter, Kylie, admits that his decision to maintain roots in the Philadelphia area, both personally and professionally, was a bit of happenstance.

“I live 10 minutes from where I work and 10 minutes from where I grew up,” says Rubin. “You just end up where you are.”

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