CBRE's CEO Brett White said at a conference call announcing the initiative that as the world's largest commercial real estate services firm it has a responsibility to be a leader in the field. "With leadership comes responsibility," he said. "We have the ability, and frankly the responsibly, to impact the way these building are managed."

Buildings in the US are responsible for 40% of the country's global warming emissions, a number that puts commercial space on par with transportation emissions, according to Ashok Gupta, of NRDC.

The specifics of how CBRE will implement this mandate on its properties are still vague. The firm plans to reduce energy consumption in large US office buildings it manages by 10% in 2008. White said every building will be looked at individually in order to pinpoint the largest ways to cut consumption. The company said in its own operations it will reduce emissions through energy efficiency initiatives. Then to offset the remaining carbon emission, White said CBRE would purchase carbon offsets. The firm estimates its operations emit 75,000 to 100,000 tons per year of CO2.

White told listeners CBRE estimates the costs of the carbon offsets will figure in the mid-six-figure range to the low-seven-figure range. He added that in the long run the savings cost for the new energy efficient components will offset any initial implementation costs.

White said he hopes other major real estate services firms will follow suit in announcing similar aggressive green initiatives. Additionally, CBRE's goal of carbon neutrality by 2010 is one leg of a large "corporate citizenship" program the firm is beginning to implement this year. White said CBRE is looking at almost 50 other areas to target ways to be more environmentally friendly. As an example he said offices around the world are investing in video and conference calling equipment in order to cut down on the amount of corporate travel.