Over the past 20 years, vaccinations have prevented over 2 million deaths. This triumph, however, has not been a panacea. Today, 1 million children in low- and middle-income countries continue to die from vaccine-preventable diseases each year. This inequality is largely fueled by technical challenges surrounding the administration of vaccines using hypodermic needles. The MEDiRoller, consists of a novel, handle applicator, containing a spring-loaded delivery system and one of our two types of single-use polymeric microneedle cartridges. The two types of cartridges include a novel cartridge containing a hexagonal solid microneedle roller, that can raster across skin to treat larger surface areas, as well as a MNP cartridge containing a sterile biomedical sponge for sterile vaccine or drug containment and loading, followed by delivery through hollow microneedles. This Big Idea, if successfully developed, will revolutionize vaccine and drug delivery in low-resource communities.