Breast cancer is a significant health problem that can affect many aspects of a woman's life. Although there is growing evidence that women with supportive husbands seem to adjust reasonably well, little is known about the impact of breast cancer among unmarried women. Relationships among primary treatment alternatives, symptom distress, perceived social support, and psychosocial adjustment to breast cancer in 101 unmarried women were investigated using data collected during the late postoperative recovery phase. The women experienced relatively low levels of psychosocial adjustment problems and perceived moderately high levels of social support. Social support and symptom distress each accounted for significant proportions of the variance in psychosocial adjustment, whereas primary treatment alternatives did not. Symptom distress emerged as the variable accounting for the most variance in psychosocial adjustment to breast cancer. Implications for health care providers to facilitate positive adjustment to breast cancer in unmarried women and directions for future studies are suggested.