The objectives for this longitudinal study were to: (a) compare colon cancer patients' and their spouses' appraisal of illness, resources, concurrent stress, and adjustment during the first year following surgery; (b) examine the influence of gender (male vs female) and role (patient vs spouse caregiver) on study variables; (c) assess the degree of correlation between patients' and spouses' adjustments; and (d) identify factors that affect adjustment to the illness. Fifty-six couples were interviewed at one week post diagnosis, and at 60 days and one year post surgery. Based on a cognitive-appraisal model of stress, the Smilkstein Stress Scale was used to measure concurrent stress; the Family APGAR, Social Support Questionnaire, and Dyadic Adjustment Scale were used to measure social resources; the Beck Hopelessness Scale and Mishel Uncertainty in Illness Scales were used to measure appraisal of illness; and the Brief Symptom Inventory and Psychosocial Adjustment to Illness Scale were used to measure psychosocial adjustment. Repeated Measures Analysis of Variance indicated that spouses reported significantly more emotional distress and less social support than patients. Gender differences were found, with women reporting more distress, more role problems, and less marital satisfaction, regardless of whether they were patient or spouse. Both patients and spouses reported decreases in their family functioning and social support, but also decreases in emotional distress over time. Moderately high autocorrelations and modest intercorrelations were found among and between patients' and spouses' adjustment scores over time. The strongest predictors of patients' role adjustment problems were hopelessness and spouses' role problems. The strongest predictors of spouses' role problems were spouses' own baseline role problems and level of marital satisfaction. Interventions need to start early in the course of illness, be family-focused, and identify the couples at risk of poorer adjustment to colon cancer.