In 2008 a project was initiated by the Transportation Association of Canada (TAC) to develop a consistent system of signs and markings for roundabouts in Canada. The goal of the project was to provide detailed information on the application of signs and markings at single-lane and multi-lane roundabouts, and recommended corresponding additions or changes to the Manual of Uniform Traffic Control Devices (MUTCD) for Canada. The project commenced with a literature review of current roundabout signing and marking practices in the United Kingdom, Australia, France, the United States and Canada, followed by a web-based survey to selected road agencies in Canada and the U.S. The objective was to gain an understanding of current signs and markings practices at roundabouts, and identify potential issues and knowledge gaps that could be studied further. Based on this, a comprehension testing procedure was developed to rationalize the various types of advance signs. The testing involved projecting a number of advance signs or sign combinations on a screen in front of test subjects, and having them fill out a form whereby they make an exit leg choice or entry lane choice after viewing the images. The outcome was the establishment of preferred types of advance signs at roundabouts. Surveys were then sent to members of the Project Steering Committee (PSC) to gauge preferences concerning a number of details related to these preferred signs, as well as other roundabout signs and markings. The outcome was a series of pavement markings, regulatory and warning signs, and guide and tourism signs for single-lane and multi-lane roundabouts, as well as several example signing and marking applications. They have all been approved by the Chief Engineers’ Council, and are expected to be published in 2012 in an update to the MUTCD. This paper discusses the project and highlights the comprehension testing procedure used to determine the preferred signs for conveying both exit leg choice and entry lane choice at multi-lane roundabouts.