A project is reported which surveyed the methods that are currently used by highway agencies to identify and treat hazardous highway elements and to determine which methods have been most successful. The synthesis specifically focuses on: (a) defining a hazardous highway element, (b) discussing methods of identifying elements that are strongly associated with accident frequency or severity, and (c) addressing funding issues and problems relative to these elements. The establishment of priorities for improving highway elements is discussed, and agency data collection problems and limitations are noted. Conclusions drawn from the study are presented and recommendations are made.  The report for this topic can be purchased at https://www.trb.org/news/blurb_detail.asp?id=3429