The authors advance an interdependence analysis of willingness to sacrifice. Support for model predictions was revealed in 6 studies (3 cross-sectional survey studies, 1 simulation experiment, 2 longitudinal studies) that used a novel self-report measure and a behavioral measure of willingness to sacrifice. Willingness to sacrifice was associated with strong commitment, high satisfaction, poor alternatives, and high investments; feelings of commitment largely mediated the associations of these variables with willingness to sacrifice. Moreover, willingness to sacrifice was associated with superior couple functioning, operationalized in terms of level of dyadic adjustment and probability of couple persistence. In predicting adjustment, willingness to sacrifice accounted for significant variance beyond commitment, partially mediating the link between commitment and adjustment; such mediation was not significant for persistence.