Highway funding in the United States has traditionally been done through user fees, most notably motor vehicle fuel taxes. However, there are growing concerns among some policymakers that fuel taxes are no longer adequate, sustainable, efficient, or equitable. Entities in the United States and abroad have conducted pilot projects or implemented mileage-based fees, including several specifically designed for heavy trucks. There are two major concerns related to truck travel: (1) heavy trucks consume a great deal of roadway capacity due to their size, operating characteristics, and annual miles traveled; and (2) roadway wear and tear caused by the combination of truck mileage and heavy loads is significant and disproportionate to the number of trucks on the road. The concept of mileage-based user fees has seen increasing support from a number of groups in recent years; however, it faces opposition from many in the general public and from the trucking industry. This paper is part of a larger effort exploring the benefits to the freight industry of mileage-based user fees, while highlighting industry concerns over its implementation.