"Widowhood is a stressful life event that requires the surviving spouse to cope not only with emotional distress but also with the loss of important social support. While much research has examined psychological consequences of spousal loss, considerably less attention has been focused on the impact of widowhood on one’s social relationships. My dissertation addresses this gap in three papers. The first paper examines the effect of widowhood on changes in various types of social support (e.g., the availability of a confidant, support from children, and support from friends and relatives). The second paper explores the extent to which widowhood brings changes to positive support (e.g., willing to listen and caring) and negative support (e.g., being critical and demanding), and how this influence varies by gender. The third paper examines whether changes in social relationships following spousal loss are significantly associated with widowed persons’ psychological adjustment. Analyses are based on data from the Changing Lives of Older Couples (CLOC), a prospective study of 1,532 married individuals aged 65 and older. Findings suggest that widowhood involves both gains and losses in social support: widowed persons are less likely to have a confidant than their married counterparts, yet they receive extended support from children and friends. The effect of widowhood varies across different time frames. In the short run, widowhood decreases negative support from family and friends; over time, widowhood does not affect children’s support, yet it increases positive support and decreases negative support from friends. An increase in support from children is associated with lower depression among widowed older adults, while changes in friends’ support do not significantly influence widowed persons’ depression. This study contributes to our understanding of the social consequences of late-life spousal loss and provides guidance for developing more fine-tuned policies and services for widowed older adults."