Over the past century, there has been a significant change in the way that the majority of the world population lives. Cities face increased threats of health challenges, such as infectious disease like HIV/AIDS, HCV, tuberculosis, pneumonia, and measles. In cities, there are also typically more dramatic differences in health between communities, meaning that one neighborhood might have amazing health and the one right next to it might be suffering. Here, at NYU GPH, we are actively researching these impacts on city dwellers. Being located in the heart of the most populated city in the United States, we thrive in this field. We teach our students how to break down these complex issues and train them to understand how all these pieces work together.