Background. The Department of Defense is actively engaged in the research and development of vaccine(s) to mitigate the burden of disease associated with diarrhea among deployed troops. Soldiers' attitudes and beliefs toward predeployment vaccines and participation in experimental research with vaccines are unknown. Methods. To assess these attitudes, a survey was distributed among soldiers who had been and were currently deployed to Operations Iraqi and Enduring Freedom. Results. Sixty-one percent of soldiers believe that predeployment vaccines are important, and 21% are hesitant to receive these vaccinations. Fifteen percent of soldiers stated that they would be willing to enroll in a study evaluating experimental vaccines, and 14% stated that they would participate in military research for vaccine development. Both male and female soldiers agreed that predeployment vaccines were important (86 and 92%, respectively); however, compared to their male counterparts, females were more hesitant to receive routine vaccinations (45% vs 37%) and less likely to volunteer for an experimental vaccine study (12% vs 20%). Officers and Air Force personnel were less hesitant to receive routine vaccinations compared to enlisted and other service personnel, respectively. Furthermore, if a soldier experienced three or more episodes of diarrhea, he or she was more likely to try an experimental vaccine to prevent diarrhea (23% vs 13%, p < 0.0001). Conclusions. A disconnect exists between the belief that immunizations are important and the hesitancy to receive them. Future studies should be directed to understand this gap and emphasize the critical importance of vaccines for health of US personnel in garrison and on deployment.