BACKGROUND: Heightened risks of cognitive impairment, disability, and barriers to care among sexual and gender minority (SGM) older adults are well documented. To date, culturally responsive evidence-based dementia interventions for this population do not exist. OBJECTIVE: This study describes the design of the first randomized controlled trial (RCT) testing a culturally responsive cognitive behavioral and empowerment intervention, Innovations in Dementia Empowerment and Action (IDEA), developed to address the unique needs of SGM older adults living with dementia and care partners. METHODS: IDEA is a culturally enhanced version of Reducing Disability in Alzheimer's Disease (RDAD), an efficacious, non-pharmaceutical intervention for people with dementia and care partners. We utilized a staggered multiple baseline design with the goal to enroll 150 dyads randomized into two arms of 75 dyads each, enhanced IDEA and standard RDAD. RESULTS: IDEA was adapted using findings from the longitudinal National Health, Aging, and Sexuality/Gender study, which identified modifiable factors for SGM older adults, including SGM-specific discrimination and stigma, health behaviors, and support networks. The adapted intervention employed the original RDAD strategies and enhanced them with culturally responsive empowerment practices designed to cultivate engagement, efficacy, and support mobilization. Outcomes include adherence to physical activity, reduction in perceived stress and stigma, and increased physical functioning, efficacy, social support, engagement, and resource use. CONCLUSION: IDEA addresses contemporary issues for underserved populations living with dementia and their care partners. Our findings will have important implications for marginalized communities by integrating and evaluating the importance of cultural responsiveness in dementia and caregiving interventions.