This study analyzes the factors influencing the adoption of Intelligent Transportation Systems (ITS) technologies in the U.S. amongst state and local transportation agencies. Using data from the ITS Deployment Tracking survey, insight is provided on how economic and demographic factors influence ITS adoption/deployment, the role safety or mobility problems play in the decision to adopt/deploy ITS technologies, and how policy can affect ITS adoption/deployment. In addition, this study examines the historical adoption patterns of ITS technologies as they entered the market place. Results indicate ITS markets are primarily made up of imitators (as opposed to innovators) and at the aggregate level the markets examined are mature. Key factors affecting the adoption and deployment of ITS include agency funding levels and the presence of a regional architecture. Based on these results, policy recommendations are presented on how best the USDOT might target its efforts to influence the pattern of ITS adoption.