This article extends the findings from the Resources for Enhancing Alzheimer's Caregiver Health (REACH II) program, a multisite randomized clinical trial of a multicomponent psychosocial intervention, to improve the well-being of informal caregivers (CGs) of persons with dementia. We used residual change scores and stepwise hierarchical regression analyses to explore separately in 3 racial ethnic groups (Hispanic or Latino, Black or African American, and White or Caucasian) how the effects of the intervention were moderated by CG characteristics (sex, age, education, and relationship), CG resources (social support), and religious coping. The results indicated that CG's age and religious coping moderated the effects of the intervention for Hispanics and Blacks. The older Hispanic and Black CGs who received the intervention reported a decrease in CG burden from baseline to follow-up. Black CGs with less religious coping who received the intervention also reported a decrease in depressive symptoms from baseline to follow-up.