To provide a framework for understanding system-based problems, this study developed a classification scheme using more than 2000 incidents reported to the Australian Incident Monitoring Study (AIMS). Using a computerized model, incidents and events were organized into a hierarchical and interrelated framework in developing a categorization “tree.” The authors describe this model in detail, present examples of this Generic Occurrence Classification (GOC) operationally, and report on results from testing the framework with different events from another reporting system. They suggest that this system offers a reliable and validated method to compare and, more important, prevent incidents and accidents from various reporting sources.