The article discusses the importance of accounting for greenhouse gas emissions and the need for global accounting standards. It highlights the use of cap-and-trade programs as a common method to limit emissions and the challenges in providing clear accounting guidance. The Environmental Protection Agency estimates that carbon dioxide makes up a significant portion of emissions in the U.S., contributing to global warming. Standard setters are working to address the lack of consistent accounting practices in this area, with a final standard expected in 2010.