Center for Aging with Serious Illness (CASI) - This Phase I Centers of Biomedical Research Excellence (COBRE) proposal establishes the Center for Aging with Serious Illness (CASI) at Dartmouth Health (DH). The growing number of older adults living with chronic, serious illness represents one of the most pressing public health challenges in the United States. However, research addressing the unique needs of this population has not kept pace with its rapid expansion. Building a robust evidence base to improve the quality of life for this group is critical to advancing healthcare. To address this gap, it is essential that research be designed to navigate the complexities of providing care for older adults facing serious illness. The primary goal of this COBRE is to create the foundational infrastructure required to develop a multidisciplinary research program focused on aging with serious illness al DH, one of the most rural academic medical centers in the country. This program will provide expert mentorship, protected research time, and institutional support to recruit and nurture a critical mass of early-career clinician-scientists, facilitating their transition into independent researchers dedicated to improving care for older adults with serious illness. To achieve this overarching goal, CASI will pursue three specific aims: (1) Establish a robust framework that integrates research expertise and mentorship to formalize CASI and strengthen DH's research infrastructure, in collaboration with affiliate institutions; (2) Develop a structured pathway to support early-career clinicianscientists as Research Project Leaders (RPLs) and enhance their transition to independent investigators through tailored, milestone-driven research plans; and, (3) Ensure the success of RPLs and Pilot Project Leaders by providing comprehensive technical assistance through the Biostatistics, Ethics, Data Management, Research Design, and Community Engagement (BEDRoC) Core, which will serve the broader DH research community focused on improving care for older adults with serious illness. CASI will concentrate on building a network of experts who will conduct clinical, behavioral, and health services research to address the challenges faced by older adults with serious illness. Our investigators will focus on solving key issues in aging with serious illness and use their findings to inform healthcare policy and stakeholder decision-making. The initial three RPLs will focus on shared decision-making for surgery in older adults, palliative care for older patients with cancer, and management of osteoarthritis in older adults with multimorbidity. The BEDRoC Core will support CASI by: (1) Providing the three RPLs specialized expertise in statistical analysis, research ethics, and community engagement to aid in the planning and execution of their projects, and (2) Creating an innovative learning collaborative that provides workshops, tutorials, resources, and services to promote continuous researcher development. COBRE funding, combined with substantial institutional investment and plans to hire additional faculty, will lay a strong foundation for creating a self-sustaining, vibrant Center. This Center will foster independent investigators whose work will ultimately improve the care and quality of life for older adults.