Two years after the start of the COVID-19 pandemic, the world has witnessed the largest vaccination effort in history. Successful delivery of vaccines has been the global hope to end this public health crisis. Countries have relied on highly scalable, reliable, and efficient digital systems and digital health solutions to organize the orchestration at record breaking speed of mass vaccination programs. These solutions support functions across the whole vaccine deployment lifecycle, from planning and management, to supply and distribution, program delivery, and post vaccination monitoring and care. The World Health Organization (WHO) is already warning about the need to prepare the next pandemic that will disrupt the world and potentially lead to the death of millions of people, which is unfortunately a statistical certainty. It is all the more important that we take stock of the successes and challenges of the COVID-19 vaccination efforts to date, continue to invest in resilient digital, health, and digital health ecosystems. Five countries were selected for these case studies, spanning multiple regions and covering a range economic contexts and levels of digital health maturity: Israel, Lebanon, Philippines, Rwanda and Tunisia. The countries were selected in large part for the speed and innovation with which they implemented digital solutions for COVID-19 vaccine delivery. The latter four benefitted from World Bank financing and technical assistance support. All these countries launched new platforms in just a few months, some within just a few weeks. The case studies were developed based on background research as well as semi-structured interviews conducted virtually with World Bank staff, government and private sector representatives involved in the vaccine rollouts.