The purpose of this chapter is to explore the relationship between ESG criteria and alternative investments by investigating the evolution of this phenomenon. Traditionally, ESG investments have been oriented towards liquid assets such as securities and bonds, due to the disclosure of information, the weight of assets under management, and rights provided to shareholders. Nowadays, ESG aspects are properly incorporated into alternative asset classes to a significant extent, thanks to their association with risk reduction and value creation. In this chapter, we first provide an overview of alternative investments, by distinguishing between the different categories and examining the key role that they have in the investment process. Second, we highlight the nexus between ESG factors and alternative investments, also describing the role of impact investment. Third, we focus on private equity (PE) investment in relation to ESG issues, indicating the ESG selection criteria in PE industry. Fourth, we discuss PE investments and ESG due diligence process. Fifth, we explore the ESG aspects in hedge fund investments, and, finally we discuss the adoption of ESG criteria in real estate investments.