The Harvard Global Health Catalyst summit is a premier yearly event bringing together leaders from across the world to share knowledge, discuss, and partner in developing innovative solutions to vexing health problems and advocating for progress towards improved health outcomes that save lives. The current main focus is on cancer, notably the emerging field of global radiation oncology, cancer prevention and advocacy. Given the importance, projected growth and newness of the field of global radiation oncology, this book chronicles the highly educational and eye-opening talks by health leaders at this growing yearly event. It serves as an educational and insightful reference for anyone interested in the rapidly growing field of global health.