Supporters of carbon neutrality say businesses and individuals can easily reduce their net climate impact. All they have to do is balance carbon emissions against the purchase of credits in environmentally friendly activities. Although the concept has its critics--including some who dispute the science--there's no disagreement that carbon neutrality is politically correct to embrace.

When asked about his company's pledge to become carbon neutral by 2012, Brett White, president and chief executive officer of CB Richard Ellis, put it like this: "Our decision is driven by our desire to do the right thing, but it is also a direct result of a rapidly evolving marketplace. A large number of our clients, both property owners and occupiers, are already actively working to reduce energy costs and create greener space."

In short, companies are adopting carbon neutral policies for both environmental and business reasons. To advance their goal of carbon neutrality, some businesses are forging alliances with environmental partners. Baxter International Inc., the pharmaceutical firm, says its carbon neutral headquarters keeps more than 11,600 tons of CO2 out of the atmosphere annually and offsets 100% of its electricity the facility consumers. It purchased Green-e certified certificates equal to 15.5 million kilowatt hours of electricity from the Chicago Climate Exchange.