In this video, Deputy Chief P.J. Norwood and Lieutenant Sean Gray discuss how fireground strategy and tactics have evolved in light of fire research conducted around the world. They discuss the fire tetrahedron and how fuel, heat, and air all affect a fire's growth or extinguishment. Gray and Norwood use the lessons learned from the research as well as their general knowledge of the fireground to illustrate safer and more effective ways to operate on the fireground. They discuss how to apply this new understanding of fire behavior to two of the fire service's most important tasks: search and fire attack.