Purpose The purpose of this paper is to analyze the different classifications of existing reference documents related to corporate social responsibility (CSR) and to propose a complementary approach of this subject in regard to ISO26000. Design/methodology/approach The publication of ISO 26000 in November 2010, an International Standard providing guidelines for CSR, seems to have modified the landscape of reference documents by bringing up the issue of legitimacy in the overview of the standards. The paper analyzes four different classifications of existing reference documents related to CSR in order to understand their approach. Findings The issue of the purpose and legitimacy of tools evoked by ISO 26000 experts enables this paper to propose a complementary approach to existing classifications, by positioning the main tools related to CSR in relation to each other. Originality/value This article presents a comparison of existing classification of CSR standards in regard to ISO26000.