Abstract: Fire is the dominant natural disturbance that shapes many temperate and boreal forest ecosystems, but climate warming and associated increased wildfire activity have led to widespread concern that forests may be less resilient now and in the future. How big can forest fires get before forests are slow to come back, if ever? How will forests regenerate following fire under future climate conditions? What happens when two severe fires occur within a few decades? I will present research that asks and answers questions along each of these three frontiers, using examples from the Northern Rocky Mountains.