Delivery is both an art and a science. We think the art is in the innovation and adaptability of the actors and different delivery models, while the science lies in replicating and scaling those models. As World Bank president Jim Yong Kim argues in his essay in this book, it’s time for the international community to compile global delivery knowledge and mobilize it for practice. Leaders in government, business, and civil society must pool their knowledge and strengths so that the most effective delivery practices can be scaled and standardized worldwide. This book is an effort to bring these stakeholders together in a conversation about the future of delivery. The needs are great—but so are the opportunities and the resources that we can mobilize if we all work together.