In the desert Southwest, changes in species composition, abundance, and distribution that may occur with climate change have significant implications for management of natural resources. These changes include: the extirpation or introduction of species, losses of biodiversity, shifts in structure and function of ecosystems and the services they provide, changes in wildlife habitat, invasion of non-native species, and changes in fire regimes. For planning, mitigation, and adaption, land managers would be greatly aided by knowing, in advance, which plant species, functional types, and assemblages will change in response to climate change so that monitoring and mitigation measures can focus on those resources.