This report in the Transit Strategies Series explores Rapid Bus. Over the past decade, much attention has been placed on the development of Bus Rapid Transit (BRT) systems. These systems provide rail-like service, but with buses, and are typically less expensive to construct than rail service. However, while costs are lower than rail, BRT systems can still be expensive. Implementation times can also be long. In order to provide many of the benefits of BRT service, many transit systems have begun operating “Rapid Bus” services. This type of service includes the elements of BRT that can be implemented on existing roadways at a lower cost and in a much shorter timeframe. Rapid Bus can also be a first step toward full-featured BRT.