This paper synthesizes the results of a project completed for the City of Edmonton in 2017 to recommend lane width values for the City’s Complete Streets Design and Construction Standards. The project included a literature review to synthesize research on the safety and speed implications of narrowed lane widths in urban areas; a jurisdictional review to document peer practice for lane widths and all-season operation in winter cities; and an in-service evaluation of the safety implications of the City’s existing lane widths. A cross-sectional population-segmented study was conducted on the effect of lane widths on safety on 626 Edmonton road segments using five years of data. Regression models were developed to understand the effect of lane width on the proportion of speeding vehicles, the frequency of all severity segment collisions, and the frequency of fatal/injury segment collisions. The main conclusion was that speed should be a primary factor in setting context-sensitive design guidelines for lane widths. The paper concludes with the lane width values incorporated into the City’s Complete Streets Design and Construction Standards. Opportunities for future research are discussed.