Adjacent track accidents (ATA) primarily refer to train accident scenarios in which derailed rail-road equipment intrudes upon (“fouls”) adjacent tracks and is potentially struck by another train on an adjacent track. ATA has been identified as one of the most important safety issues on shared passenger and freight railroad corridors. Various infrastructure, equipment and operational factors affect the probability and consequence of an ATA. The research described in this paper presents a comprehensive approach to identifying and evaluating various factors affecting the probability and consequence of ATAs. ATAs are divided into three sequential events: initial derailment, intrusion, and train presence on adjacent tracks. Each event is associated with a probability component. Factors affecting each probability component and consequence are identified and their effects are discussed. This research intends to depict a high-level overview of ATA risk and provides a basis for future quantitative risk analyses and risk mitigation measures.