This paper formulated an evaluation taxonomy to identify a broad range of factors that would be important for a comprehensive assessment. The evaluation taxonomy consists of three dimensions: road pricing strategies, impacted groups and impacts. We classified road pricing strategies by seven elements, and defined three types of impacted groups, and eleven impact types. Projects with different objectives will likely emphasize the impact types and impacted groups differently.  This evaluation taxonomy is intended to be sufficiently broad so that a wide variety of road pricing schemes can be discussed and compared in one framework.