Major events, such as a terrorist attack or a disaster, are a crucible for emergency services. Immediately, police, paramedics, and firefighters are forced to make split decisions under extreme stress and often with very little information. To make matters worse, these scenarios are frequently unique, so decision makers have little past experience to fall back on. This makes it a fascinating focus for research into decision making and planning. Dr Sara Waring is a lecturer in Forensic Psychology at the University of Liverpool and the research director for the Critical and Major Incident Psychology Research Group. She discusses the challenges emergency services face they're required to make crucial decisions under the most stressful situations imaginable.