Relationship researchers and evolutionary psychologists have been studying human mating for decades, but research inspired by these two perspectives often yields fundamentally different images of how people mate. Research in the relationship science tradition frequently emphasizes ways in which committed relationship partners are motivated to maintain their relationships (e.g., by cognitively derogating attractive alternatives), whereas research in the evolutionary tradition frequently emphasizes ways in which individuals are motivated to seek out their own reproductive interests at the expense of their partners' (e.g., by surreptitiously having sex with attractive alternatives). Rather than being incompatible, the frameworks that guide each perspective have different assumptions that can generate contrasting predictions and can lead researchers to study the same behavior in different ways. This paper, which represents the first major attempt to bring the two perspectives together in a cross-fertilization of ideas, provides a framework to understand contrasting effects and guide future research. This framework-the conflict-confluence model-characterizes evolutionary and relationship science perspectives as being arranged along a continuum reflecting the extent to which mating partners' interests are misaligned versus aligned. We illustrate the utility of this model by working to integrate relationship science and evolutionary perspectives on the role of ovulatory shifts in women's mating psychology, highlighting the tension between the desire to maintain or strengthen a bond with a current partner versus seek out extra-pair mates. To underscore the generality and generativity of the model, we also illustrate its application to two additional topics: functional perspectives on the role of subjective relationship quality, and "errors" in judgments of mate value. As scholars work to integrate relationship science and evolutionary approaches on additional topics, the promise of a unitary, functional perspective on human mating comes closer to reality.