As country-based advocacy plays a growing role in advancing policy change and ensuring accountability for health and development in the Global South, advocates and donors are increasingly seeking ways to improve their impact. The Advocacy Accelerator works to strengthen advocacy capacity, alignment, and impact by providing online and in-person platforms for advocates and their supporters to share evidence, approaches, and expertise. Our vision is a world where strong, coordinated country-based advocacy is a driving force for improvements in health and development.