The last five years saw a significant return of epidemic infectious disease, culminating in COVID-19. In our new post–COVID-19 world, how do we prevent future illnesses by expanding scientific and vaccine diplomacy and cooperation, especially to combat the problems that humans have brought on ourselves? Modern diseases and viruses have been spurred anew by war and conflict as well as shifting poverty, urbanization, climate change, and a new troubling anti-science/anti-vaccination outlook. From such twenty-first-century forces, we have seen declines in previous global health gains, with sharp increases in vaccine-preventable and neglected diseases on the Arabian Peninsula, in Venezuela, in parts of Africa, and even on the Gulf Coast of the United States. In Preventing the Next Pandemic, international vaccine scientist and tropical disease and coronavirus expert Peter J. Hotez, MD, PhD, argues that we can—and must—rely on vaccine diplomacy to address this new world order in disease and global health. Detailing his years in the lab developing new vaccines, Hotez also recounts his travels around the world to shape vaccine partnerships with people in countries both rich and poor in an attempt to head off major health problems. Building on the legacy of Dr. Albert Sabin, who developed the oral polio vaccine with Soviet scientists at the height of the Cold War, he explains how he is still working to refresh and redirect vaccine diplomacy toward neglected and newly emerging diseases. Hotez reveals how—during his Obama-era tenure as the US Science Envoy for the Middle East and North Africa, which coincided with both the rise in these geopolitical forces and climate change—he witnessed tropical infectious diseases and established vaccine partnerships that may still combat them up close. He explores why, since 2015, we've seen the decline of global cooperation and cohesion, to the detriment of those programs that are meant to benefit the most vulnerable people in the world. Unfortunately, Hotez asserts, these negative global events kick off a never-ending loop. Problems in a country may lead to disease outbreaks, but those outbreaks can lead to further problems—such as the impact of coronavirus on China's society and economy, which has been felt around the globe. Zeroing in on the sociopolitical and environmental factors that drive our most controversial and pressing global health concerns, Hotez proposes historically proven methods to soothe fraught international relations while preparing us for a safer, healthier future. He hammers home the importance of public engagement to communicate the urgency of embracing science during troubled times. Touching on a range of disease, from leishmaniasis, schistosomiasis, and Middle East Respiratory Syndrome (MERS) to COVID-19, Preventing the Next Pandemic has always been a timely goal, but it will be even more important in a COVID and post-COVID world.