Bicycling in the United States is disproportionately unsafe as a transportation mode. Despite comprising a smaller share roadway users, bicyclists are twelve times more likely to be killed in a traffic crash with a car than car occupants (Pucher and Dijkstra, 2003). Bicyclists involved in a collision with a car are three times as likely to suffer a serious injury (Rivara et al., 1997) and significantly more likely to suffer a traumatic brain injury (Juhra et al., 2012) than bicyclists in non-automobile-involved crashes. Existing research into crash causation has focused on instrumental factors (e.g. intersection type, vehicle speed) but little research has probed the role of attitudes in interactions between roadway users (Musselwhite et al., 2010). Drivers’ attitudes toward bicyclists, and how those attitudes may affect drivers’ behavior, are a largely unexplored area of research, particularly in the United States. Bringing together social psychological theories with existing techniques for measuring driver attitudes and behavior, this research utilizes an online survey to measure drivers’ explicit attitudes and self-reported behaviors and test drivers’ implicit attitudes toward bicyclists. Understanding drivers’ attitudes toward bicyclists, and whether those attitudes predict behaviors, is integral to advancing goals of community livability that incorporate safety and environmental sustainability.