The authors highlighted the importance of viewing cancer from a relationship perspective. This perspective not only considers the marital relationship as a resource that individual partners draw upon but also highlights the importance of focusing attention onto the relationship and engaging in communication behaviors aimed at sustaining and/or enhancing the relationship during stressful times. On the basis of existing conceptualizations, empiric research on couples and cancer, and the authors' perspective on the literature, they formulated the relationship intimacy model of couples' psychosocial adaptation to cancer as a first step toward building a framework for researchers and clinicians to inform their work in this area. The model proposes that patients and their partners engage in behaviors that either promote or undermine the level of closeness in their relationship and that the closeness of the marital relationship is an important determinant of patient and partner psychologic adaptation to cancer. Preliminary data from a couples' intimacy-enhancing intervention for breast cancer patients and their partners supported the model. Of the 25 couples who consented to participate in the intervention and completed the preintervention surveys, 15 couples completed all 5 sessions, and 12 couples completed the follow-up survey. The current results suggested that the intervention improved patient and partner perceptions of the closeness of their relationship and reduced their distress. The authors also discuss limitations of the relationship intimacy model as well as future directions for empiric and clinical research on couples' psychosocial adaptation to cancer. Cancer 2008. © 2008 American Cancer Society.