In this chapter, we discuss ESG ratings as a key factor in asset management. ESG ratings assess how well a company meets environmental, social, and governance standards, helping investors choose sustainable investments. We will explore the development of ESG over time and its relationship with climate change. The increase in environmental awareness and political support for sustainability has influenced public policy, leading to regulations that promote a sustainable economy. Companies adopting ESG criteria are vital to this transition, tackling challenges like climate change while fostering sustainable innovations. We outline how ESG ratings provide a way to evaluate companies beyond financial performance, guiding investors in avoiding high-risk companies. We also examine where to find these ratings, highlighting major agencies like MSCI and Bloomberg. Finally, we address the problem of differing ESG ratings among providers, which complicates the evaluation of companies’ ESG performance and discourages improvements in ESG practices.