This description appeared in a Business Week article by Douglas MacMillan :

“Even as Mozilla’s internal staff has grown to 250, from 15 in 2005, an army of volunteers still contributes about 40% of the company’s work, which ranges from tweaks to the programming code to designing the Firefox logo.

How Mozilla channels those efforts is a model for a growing number of companies trying to tap into the collective talents of large pools of software developers and other enthusiasts of a product, brand, or idea. “There’s structure in it,” says Mike Beltzner, who runs Firefox. “But at the same time you allow people to innovate and to explore and [give them] the freedom to do what they want along those edges—that’s where innovation tends to happen in startling and unexpected ways.”

At Firefox, Beltzer calls it “leading from behind.” His team makes only the highest, direction-setting decisions, such as the date each new version of Firefox has to ship. It’s up to Mozilla staff and volunteers to meet those deadlines through a process of identifying specific tasks that need to be done and accomplishing them. A system of recognition has formed among volunteers, who can be designated as “module owners” and given authority over certain areas, such as the layout.

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Getting people to donate labor may be easier for Mozilla, which operates under a nonprofit umbrella foundation. Still, the Mozilla model holds lessons for a broad range of companies. “The profit motive wouldn’t matter if the company is committed to fostering community and openness,” says Kevin Gerich, a Web development manager at International Data Group who has contributed to Mozilla on and off since 2002.

One of the biggest breakthroughs in the newest version, Firefox 3.5, came from an outside contributor. The organization wanted to include a feature to let users surf the Web without recording their history in the browser, but abandoned the idea when its developers couldn’t get it to work. With the deadline approaching, a volunteer came up with a plan for such a feature that Beltzer describes as “absolutely perfect.” A private browsing mode made it into the release.”