In events such as earthquakes or terrorist attacks, hospitals may be victims of disasters. They may need to transfer patients to outside facilities rather than continue to provide on-site care. Following the Northridge earthquake, eight hospitals in the damaged area were the foci of a United States National Science Foundation study that examined the status of the hospitals' pre-event planning, post-event evacuation decision-making, and internal and external evacuation processes. Building on this experience, this paper offers a standardized data collection tool, which will enable researchers to record hospital evacuation information in a systematic manner so that comparable data can be accumulated, evacuation research methods can be improved, and consensus on methods can be reached. The study's principal subjects include: (1) hospital demographics; (2) description of existing disaster response plans; (3) an event's impacts on hospital operations; (4) decision-making and incident command; (5) movement of patients within the facility; (6) movement of patients to off-site institutions; and (7) hospital recovery.