Expenditures for maintenance are not keeping pace with the needs of the nations highways. Desirable maintenance activity is not being carried out, and the backlog of work needed to restore the facility to good condition is growing. Difficult judgments must be made in deciding to defer maintenance. To effectively manage a maintenance program, levels of service must be able to be defined, measured, and evaluated. This report of the Transportation Research Board reviews concepts for quantifying maintenance needs, setting priorities, and developing strategies. Relevant studies in progress are discussed and additional research needs are outlined.  The report for this topic can be purchased at https://www.trb.org/news/blurb_detail.asp?id=3498