This Company Will Deliver Groceries to Your Door in Under an Hour Max Mullen is bringing new meaning to the phrase 'fast food.'

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There is an art to picking the perfect avocado—that is just one of the lessons Max Mullen learned in the process of launching his online grocery-delivery service, Instacart.

"In the beginning, everyone said it would never work," recalls Mullen, 29. He knew that several startups had tried and failed to develop effective means of delivering groceries to consumers. "But people shop for groceries all the time, and that made this a valuable problem to solve."