This book presents an integrative theoretical framework detailing five biopsychosocial mediating pathways linking family economic adversity to physical health and well-being in later years, with particular attention to how enduring couple relationships shape these outcomes and create dyadic dependencies. This framework integrates material, physiological, psychological, behavioral, and psychosocial resource pathways as well as potential modifiers of these pathways. Empirical and theoretical evidence from multiple research traditions such as life course, relational, family stress and common fate theories are synthesized to support the proposed framework. To explain the connection between family economic adversity and later life physical health and well-being, this framework takes a long-view and considers midlife as a stage with deep connections to both the preceding early middle years and the subsequent later years. This framework can be used to derive testable and comprehensive longitudinal, dyadic models in future research. Specific directions for future research are recommended.