This book introduces green bonds and their significance in portfolio management and sustainable finance. It emphasizes the significance of green bonds in terms of two primary factors: environmental sustainability and investor return. The book establishes the definitions, features, and typology of green bonds, and explains the characteristics that separate it from traditional ones. It delves into the benefits and challenges of investing in these financial instruments, and outlines the process by which green bonds are certified, focusing on the widely accepted Climate Bonds Standard. It also covers transparency, reporting, and monitoring measurements of green bonds. In its second section, the book focuses on investor and policy perspectives. The authors discuss asset allocation strategies for investors as well as various methods for integrating ESG issues into investment portfolio design. New estimating methodologies and case studies of successful green bond investments are also provided. Pitched at graduate students and researchers in finance, accounting, as well as related fields of energy and environmental economics, this book will also interest practitioners and investors looking to understand this emerging area in finance.