What do you get when you make somebody else’s partner your own? An analysis of relationships formed via mate poaching

• Three studies examined links between mate poaching and relationship dysfunction.
• Mate poached partners reported more relationship dysfunction.
• Conflicting evidence regarding whether functional differences grew over time.
• Unrestricted sociosexuality important explanatory variable.
• New measure of mate poached status introduced that reduces measurement ambiguity.

It is well documented that many relationships form via mate poaching (i.e., stealing someone’s partner), but almost nothing is known about how these relationships function. Across three studies, we observed reliable evidence that individuals who were poached by their current romantic partners were less committed, less satisfied, and less invested in their relationships. They also paid more attention to romantic alternatives, perceived their alternatives to be of higher quality, and engaged in higher rates of infidelity compared to non-poached participants. Two longitudinal studies offered conflicting evidence regarding whether relationship dysfunction associated with mate poaching develops over time or is a stable quality. Evidence from a cross-sectional study suggests that individual differences in sociosexual-orientation help to explain link between mate poaching and relationship dysfunction.