Across the state, region, and nation highway safety investigators have developed a wide variety of tools and techniques for highway safety investigation procedures. Analysis techniques can range from systematic evaluation approaches such as the Oregon Department of Transportation’s (ODOT’s) Safety Priority Index System (SPIS) down to specific localized safety assessment strategies. It is important to develop consistent methods for safety evaluations across Oregon to ensure that safety investigations are conducted in a similar manner. It is also important to develop a screening process for proper highway safety investigations and document the procedures used for this assessment. The objective of this manual is to provide a resource to assist ODOT traffic investigators with highway safety project screening and evaluations. Though the content of this manual is targeted for use within ODOT, the procedures outlined could be easily adapted by local jurisdictions for similar highway safety assessments. This manual, therefore, includes checklists and analysis procedures suitable for a variety of field and office safety investigations and assessments. This manual also includes information about the ODOT highway safety programs and tools, linkage to current standards and resources where design and operations methods are stipulated, a comprehensive procedure for safety investigation at both intersection and highway segments, and countermeasure definition and guidance.