Contract maintenance is one of a number of tools used by transportation agencies to meet their objectives or mission. This guide summarizes current contract maintenance practices for transportation systems, and is meant to provide an overview of current practices to those agencies that are considering the use of contract maintenance. Its content is based on the experience and practice of other agencies that have been using these types of contracts, but it is not meant to advocate the use of contracts or to provide a cookbook approach or handbook to such activities. However, while this guide is not meant to serve as a handbook, it does contain sufficient information to differentiate between the types of contract maintenance currently being used, to identify some of the important issues that should be considered in developing a contract, and to illustrate the potential benefits through case studies. This guide updates two earlier publications: in 1964 the American Association of State Highway Officials (AASHO) released An Informational Guide for Methods and Procedures in Contract Maintenance, and in 1987, A Guide for Methods and Procedures in Contract Maintenance (AASHTO) was published.