There is a pressing need among state and local highway agencies to develop better highway accident analysis systems. This report is intended to expand on NCHRP Synthesis 21, which is a detailed summary of the types and uses of highway location reference methods. The total highway accident analysis system is discussed here, including the storing, maintaining, retrieving, and analysis of information related to highway locations. This report focuses on the use of data files to ( a) identify high accident locations and features, (b) produce desired accident summaries, (c) process information for countermeasure selection, and (d) evaluate the effectiveness of countermeasures. The use of data systems by police agencies and for research purposes is also discussed. The required resources and the impediments to data processing and analysis are addressed, based on information supplied by state and local highway agencies. Finally, recommendations for improving highway accident analysis systems are provided.   The report for this topic can be purchased at https://www.trb.org/news/blurb_detail.asp?id=3466