A comprehensive comparison of couples' adjustment to benign (n = 73 couples) and malignant breast disease (n = 58 couples) at the time of diagnosis and at two follow-up assessments at 60 days and 1 year is reported. Specific objectives were to: (a) compare the concurrent stress, resources, appraisal, and patterns of adjustment of couples in the benign and malignant groups; (b) compare the psychosocial responses of patients versus spouses; and (c) determine the amount of correspondence in levels of adjustment reported by patients and their husbands over time. Multiple instruments with reported reliability and validity were used to measure study variables: Smilkstein Stress Scale, Dyadic Adjustment Scale, Family APGAR, Social Support Questionnaire, Mishel Uncertainty in Illness Scale, Beck Hopelessness Scale, Brief Symptom Inventory, and Psychosocial Adjustment to Illness Scale. Mixed design analyses of covariance (ANCOVA) were used to assess differences between and among couples and examine changes in study variables over time. Significant differences were found in the resources, appraisal, and patterns of adjustment reported by couples in the benign and malignant groups. Couples facing breast cancer reported greater decreases in their marital and family functioning, more uncertain appraisals, and more adjustment problems associated with the illness. In addition, there was a high degree of correspondence between the levels of adjustment reported by women with breast cancer and their husbands over time. Couples who reported high distress or a high number of role problems at diagnosis were likely to remain highly distressed at 60 days and 1 year. Study findings underscore the importance of assisting couples, not just patients, to manage the adjustment difficulties associated with breast cancer.