PROJECT SUMMARY/ABSTRACT (HUMAN PHENOTYPING CORE; HPC) The Human Phenotyping Core (HPC) and its two sub-cores (Energy Balance Sub-core and Behavioral Sub- core) directly support the research of NORC members by providing innovative clinical and intervention services to phenotype humans in mechanistic, clinical, and translational studies. The HPC supports research projects on “nutrition, obesity, and metabolic health through the lifespan”, which is the overall theme of the Pennington/Louisiana NORC. The services of t h e Energy Balance Sub-core include methods to quantify body composition, energy expenditure, carbohydrate metabolism, and cardiorespiratory fitness. The services of the Behavioral Sub-core include behavioral, cognitive, and psychological assessments; measurement of food intake in laboratory and free-living conditions; design and delivery of behavioral change interventions; and assessment of activity and sedentary behavior in free-living conditions. The HPC has a 15-year history of: a) providing comprehensive services for phenotyping individuals throughout the lifespan, b) developing, validating, and establishing quality control procedures for innovative phenotyping methods and interventions, a n d c) establishing a large base of core users. Over the last cycle (years 11- 15), the HPC was rated very highly by NORC members and was exceptionally productive, having supported 94 projects and 194 publications. The HPC also expanded its imaging capabilities and established the Pennington/Louisiana NORC Biorepository over the last cycle. The Aims of the current renewal application to fund years 16-20 (2021-2025) are to: 1) provide members with consultation, specialist expertise and a comprehensive suite of innovative energy balance and behavioral services to characterize human subjects and continue to develop unique and cutting- edge phenotyping services, 2) promote translational research by supporting “bench to bedside and back again” projects, as well as research to evaluate the translation and implementation of empirically supported treatments in clinics in the community, 3) provide training on nutrition and obesity research and human phenotyping via the planned Nutrition and Obesity Research Methods courses, and continue to facilitate pilot and feasibility studies that rely on the HPC, including use of, and contributions to, the Pennington/Louisiana NORC Biorepository, and 4) expand the data biorepository to include metabolic tissues (muscle, adipose) and biospecimens from special populations (pregnant and lactating women and bariatric surgery) that are needed for ongoing fundamental and translational studies of nutrition, obesity, and metabolic health throughout the lifespan.