Most persons with dementia are cared for by family members who are so overwhelmed that their mental and physical health declines. Adult day care programs (ADC) are growing in number to meet caregivers' needs for respite but little is known about their effect on enrollee mental health. We examined mental health of enrollees (stress, anxiety, mood, emotions) and arousal (blood pressure and salivary cortisol) from day program enrollment to 3 months following enrollment. Results showed significant decreases in morning cortisol level at 1 and 3 months (p = .047). Perceived stress decreased at 1 and 3 months measured by Perceived Stress Scale (p = .03) and Index of Clinical Stress (p = .01). Results provide support for ADC as a stress-reducing environment for individuals with mild to moderate cognitive impairment. Future studies should be conducted to examine which elements of ADC are beneficial.