On May 11, 2020, a harmonized and collaborative approach to the clinical testing, scale-up and distribution of candidate vaccines to prevent COVID-19 is essential, scientific leaders wrote in a perspective published today in Science. As the COVID-19 pandemic continues, government, industry and academia have introduced a variety of vaccine candidates. The authors note that more than one effective vaccine approach likely will be required to successfully protect the global community from SARS-CoV-2, the virus that causes COVID-19. They describe a strategic approach to research and development that would generate essential data for multiple vaccine candidates in parallel.