The development of safe and effective vaccines has been one of the greatest public achievements of the 20th century. However, there is still considerable public debate about the relative health costs and benefits of vaccines, and the information and misinformation spread through these debates can have a direct impact on vaccination and whether or not herd immunity will continue in the United States for different diseases. To understand perceptions of vaccine risks and effectiveness among young adults in the U.S., this study describes Arizona State University students' perceptions of the harms and benefits of vaccines. A preliminary free list (n=30) identified what vaccines ASU college students were most likely to recall spontaneously. The six vaccines most commonly mentioned by ASU students were: influenza (flu), chickenpox, HPV, polio, MMR, and smallpox. Using these top six vaccines, we then developed a second survey about the knowledge and perceptions of each of these vaccines and vaccines as a whole. We found that students generally perceived vaccines as safe and important to their health, but they maintained an overall lack of understanding of how vaccines work and what they protect against. While this study is only a preliminary investigation into the perceptions of ASU college students on six commonly mentioned vaccines, this could lead to investigations on how to educate and promote the usage of vaccines to college students.