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Sagebrush steppe ecosystems provide valuable rangeland and biodiversity conservation habitat in the western U.S. Remaining sagebrush steppe communities are subject to multiple anthropogenic disturbances including overgrazing and invasion by exotic annual grasses, which has shortened fire return intervals. Management decisions in these communities would be simplified if it was possible to identify past interactions between site attributes and disturbance types that predispose certain areas to degradation. We explored compositional change from 1991-2002 in sagebrush steppe communities on the Yakima Training Center (YTC) in central Washington state. Data were drawn from permanent plots established across YTC through the Land Condition Trend Analysis program. Communities varied in initial species composition and extent of invasion, and also spanned a large spatial extent, enabling examination of change along edaphic and elevational gradients. We related multivariate community responses to yearly climate, grazing pressure, fire history, and military disturbance. Specifically, we used multivariate control charts to identify transitions away from baseline conditions. Though restoration activities were sparse during the 1990s, this approach would also be suited to examining responses to restoration if conducted at large enough scale. Overall, we found strong evidence that sensitivity to drivers was contingent upon initial species composition and environmental conditions. On average, low elevation communities dominated by exotic annuals experienced the greatest change over time, while higher elevation communities (typically comprising more intact sagebrush and bunchgrass-forb associations) were more resistant to change. Fire responses were greatest in these low elevation exotic communities, which tended to become more invaded over time. Compositional change appeared to track patterns in precipitation over the study period, but was exacerbated by grazing pressure and disturbance from military training activities. In light of these results, we discuss options for conservation of intact communities and prioritizing restoration in vulnerable communities that may require the most active management inputs.