In a recent JFSP-funded synthesis of the effects of fire in the Great Basin, Miller et al. (2013) stated that largest gaps in our understanding of sagebrush dominated ecosystems were 1) a lack of long-term fire studies (>10 years) and 2) studies that evaluated the effects of repeated burns. This proposed study will directly address both of these gaps. By conducting four parallel field and fire modeling experiments, we propose to quantify the long term influence of past fires (12-30 years) on fuel loads, vegetation composition, and subsequent wildfire behavior, effects, and management in the three dominant big sagebrush ecosystems of the Northern Great Basin and Columbia Plateau. We will sample long term and repeated effects of fires in Wyoming big sage, basin big sage, and mountain big sagebrush communities. We will then use spatial fire modeling techniques to identify where past fires have altered fuel loads such that the potential for future fire is impacted, and how long following fire these impacts remain. In each sagebrush community, we have located previously burned sites where prefire composition, fuels, and fire behavior data were previously collected. Together, these experiments determine how past wildfires of differing ages and cover types influence patterns of fuels recovery and the potential for additional fire in the sagebrush steppe.