My dissertation examines how interracial couples challenge existing racial boundaries while also considering the implications the U.S. racial structure has on interracial intimacy. More specifically, I compare black-Latinx and Latinx-white interracial married couples to see how their race-based experiences vary depending on the racial composition within their union. To understand the different mechanisms through which the U.S. racial structure affects interracial marriage, I conducted interviews with 15 black-Latinx and 15 Latinx-white married couples. My research expands the current literature on interracial intimacy to include an understanding of dual-minority couples in contrast to the heavily studied white-nonwhite couples. In the first chapter I explain the history of interracial intimacy in the U.S. to contextualize the ramifications of current and historical race relations on interracial intimacy. I also detail my methodological approach, data analysis, research questions, and outline the organization of my dissertation. In Chapter 2, I examine how family members directly and indirectly transmit racialized messages about interracial intimacy, social position, and acceptability. These racialized messages, I find, directly affect rates of interracial intimacy and reinforce racial boundaries. In Chapter 3, I examine how parents racially identify their biracial children in an effort to better understand how phenotype, along with racial stratification, influence the racial identification process. I find that variations in skin tone affect whether parents choose to identify their children as monoracial, biracial, or take on a mixed family identity- all of which are tied to parents’ perceptions of how their children fit into the U.S. racial structure. In my final empirical chapter, I use interracial marriage as a framework to challenge traditional assimilation theories. I argue that interracial marriages challenge traditional assimilation theories but also reinforce racial boundaries, particularly when Latinx partners create a shared racial narrative and deny their spouses whiteness and when black-Latinx couples create a dual-minority shared racial narrative that relies heavily on their shared experiences of marginalization as racialized minorities. I argue that racial stratification not only continues to affect interracial intimacy but also show the various ways interracial intimacy challenges and reinforces racial boundaries.