PROJECT SUMMARY/ABSTRACT Advance care planning (ACP) is the process that allows individuals to express their future health care values and preferences, so that these wishes can be enacted in the event that they become incapacitated and unable to participate in their own health care decisions. In the case of Alzheimer’s disease and related dementias (ADRD), the person with dementia (care recipient), almost inevitably loses decisional capacity toward the end of life, given the progressive decline in cognitive functioning that accompanies the disease over time. The care partners to persons with dementia, most often family members such as spouse/partners and adult children, are therefore tasked with making end-of-life decisions on behalf of the care recipient with ADRD. These care partners are not always well-informed of the care recipient’s end-of-life values and preferences, and therefore may not feel confident in their ability to make decisions regarding care and treatment at the end of life, resulting in unnecessary, futile, and often unwanted medical treatments and interventions. Oftentimes, families do not want to engage in these challenging conversations and wait too long, whereby the care recipient with ADRD no longer has decisional ability to participate in the advance care planning process. We developed “The LEAD Guide” (Life-Planning in Early Alzheimer’s and Dementia), as a tool to help persons with preclinical awareness of ADRD risk and those with early-stage cognitive impairment to begin these important conversations with a care partner. With funding from the National Alzheimer’s Association, we have created a preliminary interactive LEAD Intervention that combines the LEAD Guide with educational materials about the importance of having conversations about, documenting (advance directive), and sharing ACP wishes with other family members and health care providers. This proposal outlines a mixed-method research study where we aim to: 1) evaluate the usability, accepability, feasability, and initial efficacy of the LEAD Intervention as a self-administered, dementia-focused web-based tool that can be used to facilitate the ACP process for 60 diverse community- dwelling pairs consisting of persons in the preclinical or early stage of ADRD and their care partner, 2) assess the initial efficacy of the LEAD Intervention on decision-making confidence, relationship quality, subjective well- being, and anxiety in both the care recipient and care partner, and 3) examine if the process of ACP congruence (shared understanding of the care recipients’ values and preferences regarding EOL care) as the primary factor related to changes observed during the LEAD intervention. Results from this study have the potential to guide and accelerate the implementation of the LEAD Intervention to community and health care practice, where a dementia-focused ACP process is needed.