Marc Ecko got into business by spray painting T-shirts, sweatshirts, and jackets, then driving them to shops and street fairs.

Fifteen years later, at age 36, he owns half of Marc Ecko Enterprises, a manufacturer of street-inspired apparel with a staff of 1,500 and reported global revenue of $1.5 billion. Ecko is the biggest company in the urbanwear category -- an achievement that is all the more notable when you consider that its main rivals (Phat Farm, Sean John, Rocawear) were started by black hip-hop royalty, and Ecko is run by two Jewish guys from New Jersey without built-in street cred.

Inc. spoke with Ecko in his raffishly lavish headquarters in the Chelsea district of Manhattan about his beginnings in Lakewood, New Jersey, an exurb of New York City, and his on-the-fly business education.