The development of RNA-based vaccines has shown to be remarkably revolutionary in the field of immunization due to their flexibility and efficacy in addressing a variety of diseases. This chapter specifically focuses on the advancement in vaccine technologies with an emphasis on mRNA vaccines, owing to their extensive use during the COVID-19 pandemic. Moreover, it provides the history and background context starting from the early stages of research on the vaccine technology to the present-day developments. It further describes the intricacies of RNA vaccines with their specific differences with mRNA and RNA interference including, among others, greater stability and delivery systems aimed at bolstering these vaccines’ potency. Emphasis is placed on recent innovations concerning delivery techniques and RNA stabilization. The case studies, especially the ones on COVID-19, cancer, and some infectious diseases, demonstrate the practical use and success of RNA vaccines. The chapter also outlines safety, immunogenicity, and production difficulties as the main hurdles for innovation. Regulatory frameworks for military and biodefense indicate that there is little to no oversight on vaccine research making it easy to disregard quality standards adding to the risk of RNA vaccine misuse. This chapter elaborates on these issues along with the boundaries of RNA vaccine regulations. Lastly, the chapter focuses on technological innovations forecasting impacts on global healthcare trends and new avenues of research for RNA vaccines. The chapter ends with describing how RNA vaccine technology works currently and what impact it has on further research and public health strategies.