摘要:The present study aims at investigating disclosure practices from a sustainability point of view in major Brazilian companies according to guidelines by GRI, Global Reporting Initiative. Additionally, disclosure is verified by taking into consideration the nature of company activities in relation to their potential for environmental impact, according to disposition by law number 10.165/2000. In order to do that, there was a qualitative research with an analysis of content of sustainability reports by 33 companies which published GRI reports in the 2009-2010 period. The results showed a high level of disclosure with a highlight on companies considered to have great potential for pollution. Besides that, it was perceived that the social indicators are the ones that provide companies with the most opportunities to talk over their practices towards collaborators and society while economic and environmental indicators proved more objective, being generally presented as illustrations. It is possible to identify the companies’ search for market legitimacy, since it is through the announcement of such information that these companies display their main measures towards the improvement of people’s lives as well as environmental preservation, which directly affect their image before stakeholders.