This project uses a practical procedure for conducting in-service road safety reviews of existing intersections. The procedure in this project is based on current experience in Canada and other countries and applies road safety engineering research to the Canadian environment. An in-service road safety review is an in-depth engineering study of an existing road using road safety priniciples with the aim of identifying cost-effective countermeasures that would improve road safety and operations for all road users. A review can be done for any road section, intersection, or interchange, and is generally most effective when conducted at locations where a high collision risk has been identified. In-service reviews typically include a structured review of collision history, geometric characteristics, and traffic, operational efficiency and could also include traffic conflict observations and a human factors assessment. The main output from in-service road safety reviews is the identification of road safety problems and the development of cost-effective countermeasures to overcome these road safety problems.