Research on "the widowhood effect" shows that mortality rates are greater among people who have recently lost a spouse. There are several medical and psychological explanations for this (e.g., "broken heart syndrome") and sociological explanations that focus on spouses' shared social-environmental exposures. We expand on sociological perspectives by arguing that couples' social connections to others play a role in this phenomenon. Using panel data on 1,169 older adults from the National Social Life, Health, and Aging Project, we find that mortality is associated with how well embedded one's spouse is in one's own social network. The widowhood effect is greater among those whose spouses were not well connected to one's other network members. We speculate that the loss of a less highly embedded spouse signals the loss of unique, valuable, nonredundant social resources from one's network. We discuss theoretical interpretations, alternative explanations, limitations, and directions for future research.