What does it mean today to be a church totally committed to the gospel and fully engaged in God’s mission? What major religious and sociological trends in our world are affecting the role of the global church and local churches? How must we understand and be prepared to face these trends? How do we define “church” in the twenty-first century, being faithful to the Scriptures and at the same time relevant to a generation that does not believe in the institutional church anymore? What are some good models of missional churches in different regions of the world that will encourage and inspire those who long to see a church making difference in society and in the world? These are some of the issues that the book you are holding in your hands addresses. There are certainly no final answers and magical forms; rather, we present a broad and deep discussion on how the gospel should be lived out by Jesus’ followers in our time and through our communities. Questions are raised and analyzed both from the perspective of a local church as well as from a global and general understanding of the Christian church. Some of our examples will focus more on local realities, others more on global challenges. The first part of the book is dedicated to a biblical and theological reflection on gospel, church, and mission. It includes Old and New Testament studies on the theological implications of being church, based on the biblical narrative. The second part deals with a variety of contemporary missiological issues related to the broader theme of church and mission. Different perspectives from current discussions and dialogues around the globe are included, covering both ideological reflections and practical aspects of being a mission-shaped church. The third part presents regional and national case studies that show the enormous creativity in church planting and engagement of local communities in their own societies. Models applied in the secularized Europe are contrasted to ways of functioning as church in fast growing congregations in the global South.