Disasters kill people, destroy infrastructure, damage ecosystems and undermine development, and could increase in frequency due to climate change. There is a need for increased awareness on the latest advances in disaster risk reduction (DRR) and climate change adaptation (CCA). A significant advancement is a better understanding of ecosystem-based approaches for reducing disaster risks and adapting to climate change. This book explains the importance of ecosystems and their management for DRR and CCA and provides guidance to plan and implement ecosystem-based disaster risk reduction and climate change adaptation (Eco-DRR/EbA). DRR aims to work on reducing risk factors, by reducing exposure, vulnerability and hazards. A number of things can contribute to increasing risk in each of the risk factors, many of which are related either directly or indirectly to poor environmental management. The international policy field acknowledges the need to improve resilience through improving, maintaining and managing ecosystem function with a number of mentions and mandates in several important agreements, such as the Sendai Framework for Disaster Risk Reduction 2015-2030 (SFDRR), the United Nations Framework Convention on Climate Change (UNFCCC), and the Convention on Biological Diversity (CBD). Ecosystems provide important services that can address all risk factors. They reduce exposure to hazards by buffering their impact, such as mangroves attenuating waves or forests protecting against avalanches. Well managed, they reduce hazards; indeed degraded ecosystems are more prone to creating hazards such as landslides or desertification. Finally, they can reduce vulnerability by providing food, water and livelihoods to communities. Eco-DRR is the sustainable management, conservation and restoration of ecosystems to reduce disaster risk, with the aim to achieve sustainable and resilient development (Estrella and Saalismaa 2013). EbA is the use of biodiversity and ecosystem services as part of an overall adaptation strategy to help people adapt to the adverse effects of climate change (CBD 2009). While these two approaches have some differences due to being developed in silos, separately in the DRR and CCA communities, there is much overlap in practice. We hope that readers of this source book will retain a few key messages about Eco-DRR/EbA and its core principles. These include: providing multiple benefits and offering a no-regrets strategy. Furthermore, ecosystem-based approaches to DRR/CCA are often more cost-effective over time than grey infrastructure alone, although in some cases, grey-green infrastructure combinations are the most optimal. And finally, gender-sensitive Eco-DRR/ EbA is fundamental to transformational resilience, or resilience which leads to sustainable reduction of disaster risks. Our book concludes that there are still knowledge gaps and challenges to mainstreaming Eco-DRR/EbA, not the least being how to scale-up investments in ecosystems for DRR/CCA from a locally specific project to generalisable guidelines. This is indeed one of the main challenges of Eco-DRR/EbA: for example, vegetation that reduces erosion in one locality may not work in another. Nevertheless, this book aims to provide answers to overcome some of these gaps and challenges. It also challenges readers to engage in new research, find ways to incorporate Eco-DRR/EbA in development planning and join the growing community of practice working to advance this emerging field.