This thesis attempted to explore how county emergency managers understand the risks most likely to manifest in their jurisdiction using an internet survey. This study addressed the following research questions: 1) What risks do county emergency managers perceive to be the most likely to manifest in their jurisdiction? 2) What factors explain their risk perceptions? Data were collected by internet survey which was sent to county emergency managers in FEMA Region V. When data collection ceased, 165 county emergency managers had completed the internet survey in full. Regression analysis revealed that a small amount of the variance in risk perception was explained. The notion of extending traditional variables professionally in a way that makes sense for county emergency managers proved to be valuable. Additionally, operationalization issues raised in this study can be used as valuable lessons learned for future risk perception research.