HOK designed the existing office towers, which accommodate more than 5,000 employees in about 1 million square feet.

By installing everything from motion detectors to waterless urinals, Adobe has reduced its electricity use by 35 percent and its gas consumption by 41 percent since 2001, at the same time that its headcount has swelled 80 percent.

More important, Adobe is proving that building green isn't just good corporate citizenship; it's plain good business. To date, the company has invested about $1.1 million in 45 energy-efficiency projects, yielding nearly $1 million in annual savings, including about $350,000 in energy rebates.

Source: "The Greenest Office in America," Business 2.0, October 16, 2006, by Jeff Nachtigal. Read the story and see how they did it.