In this dissertation, I examine how we quantify the dynamic, cumulative effects of relational social exposures with longitudinal survey data. In Chapter 1, I demonstrate a new mediation framework for describing what are often conceptualized problematically as “neighborhood effects.” Findings from this study clarify the reciprocal, life-course process through which neighborhood is implicated in the early production of social inequality. In Chapter 2, I extend this mediation framework to respond to theoretical critiques of how variables for race are used in common regression frameworks in attempts to study structural racism. I demonstrate an alternative counterfactual approach to explain how multiple racialized systems dynamically shape health over time, examining racial inequities in cardio-metabolic risk. I decompose the observed disparity into three types of effects: a controlled direct effect (“unobserved racism”), proportions attributable to interaction (“racial discrimination”), and pure indirect effects (“emergent discrimination”). I discuss the limitations of counterfactual approaches while highlighting how they can be combined with critical theories to quantify how interlocking systems produce racial health inequities. In Chapter 3, I use this framework to examine the Black-white wealth gap in the United States. Descriptive and qualitative analyses have identified many mechanisms underlying wealth correlations across successive generations, but few studies have quantified the relative contributions of these interconnected and racialized systems of reproduction to the total gap we observe today. I define a wealth gap in 2015-17 between the grandchildren of those racialized as Black and the grandchildren of those racialized as white in 1968-70. I use a fully interacted counterfactual mediation framework to decompose this disparity into the historical, racialized contributions of 1) effects of home values in 1968-70 on home values in successive generations and 2) effects via educational attainment in successive generations. Findings from this study contribute to our understanding of the dynamic, racialized process of multigenerational place-based wealth accumulation and support the importance of historically contingent social policy centered on reparative justice.