The 2010 GRI Sustainability Reporting Statistics publication indicates that 47 percent of the GRI sustainability reports obtained external assurance and that the majority of the external assurance was provided by the GRI. What are the advantages of having accountants as compared to other third party groups like the GRI provide assurance services on corporate sustainability reports?

• What are the advantages of having non-accountant third party groups, like the GRI, as compared to accountants provide assurance services on corporate sustainability reports?