As monogamy is a culturally prevalent ideal, patients often suffer shame and guilt to the extent that they fail to live up to that ideal though desiring to or to the extent they reject that ideal in favor of nonmonogamous arrangements. Recent research in social, personality, and evolutionary psychology can lead to a mode of thought that can be helpful in overcoming the cultural bias that only monogamy is adaptive and that nonmonogamous practices are most likely maladaptive and pathological. Monogamous and nonmonogamous orientations may be better predicted by personality variables than by gender and both orientations may function as adaptations for reproductive advantage, despite the costs. The implications of these ideas for clinical practice are discussed.