TREA is an objective, systematic method for developing individualized non-pharmacological treatment plans based on an analysis of the agitated person's unmet needs, past and current preferences, past role-identity, cognitive, mobility, and sensory abilities/limitations, and possible causes for particular agitated behaviors. The methodology calls for ascertaining the type of agitated behavior and the most likely etiology, and then matching the intervention to the etiology and to the participant's characteristics.