This book invites readers to explore and understand the phenomenon of hope in its various facets. The scientific framework is provided by Positive Psychology, complemented by theology and philosophy, and enriched by the authors' insights from the Hope Barometer, an ongoing study in Germany and Switzerland since 2009 that examines the significance and experience of hope in people's daily lives. The essential findings of research on hope to date can be experienced in this book: as valuable foundational knowledge for fields such as psychology, psychotherapy, medicine, nursing, education, social work, care, church, coaching, and leadership, as well as an overview of the current state of research for scholars and educators.