This study involved an in-depth evaluation of the Washington State Department of Transportation highway data development and analysis activities. It developed statistically-based procedures and recommendations for a streamlined highway data collection program. Opportunities to reduce manpower and equipment costs, streamline work activities, improve the quality of data collected and provide accurate and timely data for the various users were identified. Given the focus on highway data, the major effort was devoted to the Department's traffic counting program. However, many data items and programs were considered, with the following receiving particular attention: traffic volume counting, including estimation of annual average daily traffic at any location throughout the state highway system; associated seasonal, axle and growth factors; vehicle classification; truck weights; and the relationship between the statistical sampling requirements recommended for these items and those associated with the FHWA Highway Performance Monitoring System in the state.