TRB’s National Cooperative Highway Research Program (NCHRP) Research Results Digest 337: Design Flexibility Considerations for Built Urban Environments explores issues related to the use of roadway design exceptions or variances.  The report also examines processes designed to help manage the use of exceptions or variances, and highlights potential means to provide a timely procedure for addressing design exceptions or variances. This report is located at https://www.trb.org/news/blurb_detail.asp?id=10263