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A state and transition model (STM) depicts our current understanding of ecological dynamics on an ecological site. An STM identifies the different plant communities or �states� that may exist on a given ecological site and how other site characteristics, such as hydrology and dynamic soil properties, might change as the plant community phase or state changes. STMs have the flexibility to describe both succession driven plant community dynamics and non-linear dynamics typically associated with chronic or catastrophic disturbances. STMs describe the environmental conditions, disturbances and management actions that cause vegetation to change from one suite of plant species to a different suite of species, and the management actions needed to restore plant communities to a desired composition. The complexity of STMs has developed with maturation of the science and development of the models.� Typically STMs are associated with ecological site descriptions (ESDs) however in the western United States many landscape-scale management issues such as fuel reduction treatments or post-fire rehabilitation activities occur at scales far larger than the individual ecological site scale therefore methods for aggregating ecological sites into groups that respond similarly to the same disturbances have been developed. Disturbance Response Groups (DRGs) consisting of multiple ecological sites with one generalized STM provides an ecologically sound landscape scale management tool for multiple applications including habitat restoration, fuels management, fire rehabilitation and grazing management planning.