Assurance on Sustainability Reports: An International Comparison

Globally, companies increasingly publish separate general purpose, non-financial (sustainability) reports. Some of these are independently assured and assurers may or may not be from the auditing profession. We seek to understand this emerging voluntary assurance market. Using a sample of 2,113 companies (from 31 countries) that produced sustainability reports between 2002-2004, we use sequential logit analysis to identify the factors associated with the decision to voluntarily purchase assurance and the choice of assurance provider. We hypothesize that a company's need to enhance credibility through assurance and choice of assurance provider will be a function of company-, industry-, and country-related…