Many leading investment institutions, including asset managers, pension funds and insurance companies, have made commitments to sustainable investment or to the delivery of sustainability goals alongside their investment objectives. This mainstreaming of sustainable investment raises many important questions, such as the following: Do sustainable finance strategies lead to meaningful real-world change? Are fears about greenwashing justified? Does sustainable investment deliver better financial outcomes? And is it consistent with investors' fiduciary duties? Can the sustainability data and ratings used in finance be trusted? Does sustainability information drive improved sustainability performance? How should sustainable investment be governed? What are the roles and responsibilities of public and private actors? This book unpacks the key terms, concepts and debates - both theoretical and applied - that underpin sustainable investment. Through evidence-based analysis, it cuts through the hype to critically explore sustainable finance's transformative potential as well as its limitations. In doing so, the book enables public policymakers, financial institutions, companies, civil society organisations and academics to engage in a more informed discussion about the contribution that sustainable investment can make to sustainability goals.