This application addresses broad Challenge Area 01: Behavior, Behavioral Change, and Prevention, and specific Challenge Topic 01-AG-103: Individual-based Model of Social Behavior. Innovations in developmental theory have outpaced methodological development and application. Needed are methods that allow for precise articulation of within-person/intra individual dynamics of behavior that unfold over multiple time scales (days, years, decades). New tools that explicitly tether dynamic ideas, within-person methods, and real-world observations must be developed, implemented, and evaluated - substantively and methodologically - to advance our understanding of the dynamic social processes that influence health and well-being. Our approach to this Challenge includes the following specific aims: (1) developing and organizing analytical methods for measuring and articulating the dynamic characteristics and dynamic processes implicated in individual-based models of interpersonal/social behavior, (2) elaborating and implementing a data collection/design framework for examining the variability and change in interpersonal behavior, health, and well-being occurring at micro-, meso-, and macro- time scales (i.e., days to decades), and (3) predicting and testing how the dynamic characteristics and processes of interpersonal behavior, health, and well-being change over the course of hours/days, weeks/months and how those characteristics, processes, and changes differ across early-, mid-, and later adulthood. By deliberately tethering methodological advances to theoretical conceptions, and providing illustrations of how researchers can make use of these tethers, this project will provide a valuable resource for both methodological and substantive researchers interested in life-span development, interpersonal behavior, and health/well-being. Our research will deliver new methods and insights that allow investigators to link precisely modeled dynamic characteristics and dynamic processes of individuals'interpersonal processes to important health outcomes and well-being across early, mid-, and later adulthood. PUBLIC HEALTH RELEVANCE: Interpersonal behavior affects individuals'emotions, arousal, stress, and facilitated or impairs social support, intimacy, and relational satisfaction. This project will deliver new methods and models that allow for more specific articulation and linking of when and how interpersonal interaction processes contribute to health, well-being, and aging.