In this introduction, we give a short overview of the motivation for the book, its structure, and content. The book first discusses current physical understanding and modeling approaches of climate extremes (Chapters 2-6, 2, 3, 4, 5 and 6). Second, various methodologies to assess the impacts of climate extremes are presented, along with respective case studies, using state-of-the-art empirical, data-driven impact assessment methods, process-oriented impact models, or a combination of both (e.g., Chapters 7-11, 7, 8, 9, 10 and 11). Third, challenges and opportunities of transdisciplinary research on weather and climate extremes and its complexities along with the human-environment nexus and coupled socio-ecological systems are presented (Chapters 12-17, 12, 13, 14, 15, 16 and 17). This includes, for instance, a discussion of different risk assessment approaches from a disaster risk reduction perspective, an overview of conflict dynamics, climate history, and challenges. The book concludes with an outlook (Chapter 18) on the need for more transdisciplinary work and global collaboration of scientists and practitioners to address emergent risks and extreme events and to improve risk reduction and resilience.