The Evolving Fireground, second edition, bridges scientific fire dynamics research with street-level tactics to drive safer, smarter operations. Building on findings from UL's Fire Safety Research Institute (FSRI) and global studies, Deputy Chief P.J. Norwood and Captain Sean Gray explain how fuel, heat, and air interact to shape every incident--translating complex science into practical, coordinated action for firefighters, company officers, and incident commanders. This updated and expanded edition delivers scenario-based lessons and clear operational guidance on the fire tetrahedron, flow path control, ventilation management, survivability-focused search, fire attack that limits air entertainment and controls growth, and command-level size-up and decision frameworks. It's a modern blueprint where science meets experience--and evidence drives action on the fireground.