With so many disclosure options now to choose from-and with so much backing from investors-one might think that companies would be responding in droves to keep up with this rising demand for information. Results from the field are mixed, however. Some companies appear to be suffering from "survey fatigue," while others have yet to see the value in producing any such sustainability reports.

In the case of the Carbon Disclosure Project, which has been sending out corporate surveys for four years, the response rate to its latest survey edged up by only one percent, compared with double-digit gains in prior years. This suggests the survey "may have reached a threshold" among FT500 companies, according to an evaluation by Innovest Strategic Value Advisors for CDP.

In 2006 CDP expanded its survey beyond the FT500 to include 1,500 other major companies around the world. But the response rate among these companies did not come close to what CDP achieved within its core group of FT500 companies:

* Among U.S. companies in the S&P 500, the response rate to the CDP4 survey was only 58 percent.
* In Canada, 23 percent of the 300 surveyed companies responded.
* In Japan, 37 percent of 150 companies responded.
* In Australia, 24 percent of 150 companies responded.
* Elsewhere in Asia, only five of 40 companies responded for a mere 8 percent response rate.

The Global Reporting Initiative, which was launched in 1999, has faced a similar challenge in building its corporate participation rate. Compared to CDP, GRI has attracted more interest from European and Asian companies, but has had less buy-in among U.S. firms. This prompted a recent appeal by institutional investors urging S&P 500 companies to adopt its reporting format. Overall, the GRI has struggled for several years to raise the number of total companies much beyond 1,000 that have issued sustainability reports according to its guidelines.

Whether the Global Framework on Climate Risk Disclosure can help break this logjam remains to be seen. Framework organizers have produced a companion guide that links together the key energy and climate-related disclosure elements of CDP and GRI with mandated disclosure requirements in U.S. securities filings. The hope is that this will "help ensure that investors receive comprehensive and consistent climate-related disclosure from companies," according to Mindy Lubber, president of Ceres, a key backer of this initiative. Nevertheless, companies still have considerable leeway in how they report, and in what format-if they choose to report at all.