This book guides readers to the new concept of “Satoumi” and explains how its practice works to solve challenges in complex social-ecological systems of coastal areas. The book describes the significance of Satoumi Science as a transdisciplinary process. It starts with introducing the definition of Satoumi, highlights the important distinction between active measures (direct actions to improve ecosystem functions and services) and passive measures (a variety of management activities), and presents the concept of Integrated Local Environmental Knowledge (ILEK) as a knowledge base for Satoumi activities. It also introduces residential researchers and bilateral knowledge translators as the key actors of Satoumi co-creation through the transdisciplinary processes.