Sustainability communication is a more and more widespread necessity for marketers because of the increased sensitivity to this topic. The objective of this research is to investigate the way the largest companies in the world communicate their social and environmental commitment: sixteen companies’ websites have been analyzed in order to explore what kind of sustainability communication tools they use. Findings show that the selected companies pay attention to communicate their commitment, also in the case of those suspected to be irresponsible. Risks deriving from greenwashing are also discussed: it can be a danger for long term survival of companies.