This book offers an analytical look at the much debated risks and benefits of the newly developed COVID-19 mRNA-vaccines. As such, it is one of the first books to give a comprehensive overview of mRNA vaccines against COVID-19 and the only one that addresses this topic from a broad multidisciplinary background. It brings together insights from various underlying disciplines on the challenges of developing and evaluating the most suitable vaccines for mass vaccination programs enrolled throughout the world - focusing on safety and efficacy. This book should not be missing on the shelf of any biomedical researcher, epidemiologist, public health professional or clinical researcher interested in SARS-CoV2 or virology and vaccine development in general.