Objectives: Health psychology has contributed significantly to understanding the link between psychological factors and health and well-being, but it has not often incorporated advances in relationship science into hypothesis generation and study design. We present one example of a theoretical model, following from a major relationship theory (attachment theory) that integrates relationship constructs and processes with biopsychosocial processes and health outcomes. Method: We briefly describe attachment theory and present a general framework linking it to dyadic relationship processes (relationship behaviors, mediators, and outcomes) and health processes (physiology, affective states, health behavior, and health outcomes). We discuss the utility of the model for research in several health domains (e.g., self-regulation of health behavior, pain, chronic disease) and its implications for interventions and future research. Results: This framework revealed important gaps in knowledge about relationships and health. Future work in this area will benefit from taking into account individual differences in attachment, adopting a more explicit dyadic approach, examining more integrated models that test for mediating processes, and incorporating a broader range of relationship constructs that have implications for health. Conclusions: A theoretical framework for studying health that is based in relationship science can accelerate progress by generating new research directions designed to pinpoint the mechanisms through which close relationships promote or undermine health. Furthermore, this knowledge can be applied to develop more effective interventions to help individuals and their relationship partners with health-related challenges.