• To study the effectiveness of preventive intervention in lowering postbereavement morbidity, 200 widows were assessed in the early weeks following their husbands' deaths. Subjects at risk for postbereavement morbidity were selected and randomly allocated to experimental (N = 31) and control (N = 33) groups. Specific support for grief and encouragement of mourning was carried out with the experimental group during the first three months; no intervention was given to the control group. All were followed up 13 months later with a validated health questionnaire. There was a significant lowering of morbidity in the intervention group as compared to the control group (P <.02). The most significant impact of intervention occurred with the subgroup of intervention and control subjects who perceived their social networks as very nonsupportive during the bereavement crisis (P <.001).