Problems facing institutions are often embedded in operating practices. These can be difficult to identify precisely, although their effects may be dramatic and clearly felt in areas such as the Emergency Department, Obstetrics, or Surgery. By reviewing operating procedures, interviewing participants in the process, tracing process flows, and determining levels and event times, a model of the process can be developed. Operations Analysis and simulation models provide management the ability to resolve problems by determining the types of solutions which best meet the needs of the institution, its physicians and its clients.