To date, little research has systematically explored the retention of self-identity in dementia and its potential use for the individualization of care. The purpose of this study is to determine the impact of role-identity-based treatment for persons with dementia. We recruited a total of 93 elderly persons with dementia (mean Mini-Mental State Exam score = 10.58) for this study. Experimental (treatment) group participants were engaged in activities designed to correspond to each participant's most salient self-identity. The treatment group showed a significant increase in interest, pleasure, and involvement in activities, fewer agitated behaviors during treatment, and increased orientation in the treatment period. The experimental treatment had effects that were superior to those of the nonexperimental activities. The results highlight the powerful roles that perception of self and fulfillment of self-identity play in overall well-being.