During the K01 period, I will fill critical gaps in my training through meeting 6 training goals: 1) advance my understanding of the experiences of persons with Alzheimer’s Disease (AD) and AD-related dementias (ADRD), their care partners and older adults (co-mentor: Edith Burns, MD); 2) gain expertise in theoretical models of loneliness (team member: Louise Hawkley, PhD); 3) advance my understanding of psychotherapies (team member: Allison Applebaum, PhD); 4) leveraging technology to deliver interventions (primary mentor: Michael Diefenbach, PhD); 5) learning advanced study designs, methodologies, and statistics (co-mentor: Martin Lesser, PhD); and 6) engage in in-depth training needed to maintain a successful program of research (Diefenbach). These training goals and expert mentorship were designed in support of my overall career goal of becoming an independent investigator improving the lives of older adults and their care partners through reduction of loneliness. More than 60% of care partners of persons with AD/ADRD report feeling lonely. Building on the existing evidence that increasing meaning and purpose in life is a strong predictor of decreased loneliness, interventions to reduce loneliness in this population may be strengthened by incorporating concepts from Meaning-Centered Psychotherapy (MCP). Thus, the overall goal of the proposed project is to reduce loneliness in care partners of patients with AD/ADRD through increasing their sense of meaning and purpose in life using concepts from MCP, delivered via a web-based platform, RELOAD-C (REducing LOneliness in Alzeheimer’s Disease-Care Partners). This will be achieved through three Specific Aims. Aim 1 consists of three phases (preparatory work, stakeholder involvement with N=15 AD/ADRD care partners, and adaptation of the existing web-based platform) to produce RELOAD-C, which centralizes: 1) 6 brief videos portraying our MCP expert delivering MCP concepts; 2) links to 7 virtual group meetings (6 weekly + 1 booster) to discuss MCP concepts; and 3) written content expanding on the material from the MCP videos. Aim 2 evaluates usability/acceptability of RELOAD-C (defined as a task success rate ≥ 78%, and scores ≥ 68 on the System Usability Scale) with N=20 care partners of persons with AD/ADRD. Aim 3 proposes a pilot RCT to evaluate the preliminary efficacy of the RELOAD-C components (MCP videos vs. MCP-focused group discussions) in reducing loneliness and feasibility of conducting a future, large-scale RCT. N=96 AD/ADRD care partners will be randomized to: usual care, n=32; MCP videos alone via RELOAD-C, n=32; or MCP videos + weekly groups via RELOAD-C, n=32. Care partners’ outcomes will be assessed at baseline, and 6-weeks and 3-months post- baseline. We expect the effect sizes will be in the moderate range (.3). Feasibility is defined as: ≥ 75% consented, ≤ 30% drop-out, and 80% engagement with intervention. Reducing loneliness among care partners is of high public health significance...