People view monogamy as the optimal form of partnering and stigmatize consensual non-monogamous (CNM) relationships. Likewise, attachment researchers often equate romantic love (and security) with sexual exclusivity. Interestingly, a sizeable minority of people engage in CNM and report high levels of satisfaction. Across two studies, we examined how individual differences in attachment were associated with attitudes toward CNM, willingness to engage in CNM, and current involvement in CNM....