The use of low-grade and waste materials as alternatives to naturally occuring aggregates in the construction of roads helps to conserve the supplies of ggod quality aggregates and assists in problems arising from the disposal of unwanted materials. The report is one of a series on individual materials which is aimed at bringing together the information that is available on each of the major waste products that have roadmaking potential. It deals with spent oil shale and it considers the extent to which this type of shale can be used in road construction. The report discusses the types and quantity of shale taht are available, the purposes to which it can be put in road construction and the tests needed to ensure that shales meet the required specifications.