Although roundabouts have been shown to provide significant safety and operational benefits, transportation agencies frequently encounter public opposition to their use. Consequently, a better understanding of public perceptions of roundabouts is critical to allow transportation agencies to address this issue. This study involved the implementation of a statewide Web-based survey of road user perceptions as they relate to roundabouts, which resulted in a total of 11,972 responses from road users throughout Michigan. The results of this survey show that public perceptions were mixed: 38.9% strongly opposed the use of roundabouts and 30.6% strongly supported their use. Respondents who had more experience with roundabouts tended to be more supportive. Younger respondents showed the most support, and support tended to decrease consistently with age. Female drivers, pedestrians, motorcyclists, and commercial motor vehicle drivers were all less likely to be supportive of roundabouts, whereas bicyclists were more supportive. Respondents were also asked to assess the relative safety and operational efficiency of roundabouts compared with traditional intersection configurations. Overall, 52.7% of respondents found roundabouts to be more operationally efficient, and an equal percentage found them to be less safe. The results show that the strongest indicators of roundabout support are linked to experience, making it imperative for road agencies to orient road users effectively to facilitate public acceptance of roundabouts. The results of this study provide valuable information that can be used to target public information and education programs intelligently toward appropriate audiences.