Metropolitan areas are facing increasing congestion but financial resources to provide new or expanded transportation infrastructure will be limited in the future. Moreover, environmental constraints limit expansion of the highway footprint in urban travel corridors. This paper assesses a strategy to alleviate recurring congestion on metropolitan highway systems by adding “dynamic” capacity during peak periods using shoulders as travel lanes, along with variable peak-period user charges levied on all lanes to manage demand and pay for the capacity improvements. It presents an analysis of the traffic, delay, fuel consumption, CO2 emissions, and cost and revenue impacts. The paper then discusses various technical and public acceptance issues with regard to the concept, and how these issues might be addressed.