The global financial system faces unprecedented challenges related to climate change, social inequality, and a lack of transparency in corporate practices. Sustainable finance, integrating environmental, social, and governance (ESG) criteria into financial decisions, has emerged as a driving force for the future of global markets. There is a growing demand for transparency from investors and regulators, compelling companies to demonstrate their financial performance and social and environmental impact. Impact has become a key criterion for measuring corporate success. Investors, consumers, and governments increasingly urge companies to contribute positively to society, reduce inequality, and promote sustainability. In response, new financial instruments, such as green and social bonds, as well as impact funds, channel capital to projects that generate positive impact while promoting economic returns. Transparency is the other key pillar of sustainable finance. Without transparency, companies can conceal harmful or unethical practices. However, with new regulations and technologies like blockchain, the financial system is becoming more open and accountable. Transparency enables investors to assess ESG risks more accurately and helps companies build trust with their stakeholders. In this new paradigm, finance is no longer solely about generating profit, but also about creating social and environmental value. This book explores the crucial role of impact and transparency in building a more accountable financial system aligned with the Sustainable Development Goals.