A psychometric analysis of the Mental Adjustment to Cancer (MAC) scale was performed in a heterogeneous Swedish sample of cancer patients (n = 868). The homogeneity of the original subscales proved to be satisfactory (alpha coefficients 0.61-0.81). The sample was randomly split into two subgroups, and a factor analysis was carried out in one of them using the LISREL 8.20 procedure. This yielded four factors called 'Hopeless', 'Positive', 'Anxious' and 'Avoidant' including 28 of the 40 original items (alpha coefficients 0.58-0.81). The novel factor structure was cross-validated and confirmed in the second subgroup. In contrast to the original scale (one item), 'Avoidance', was indexed by three items. The distinction between mental adjustment and coping is discussed. It is concluded that both versions of the MAC scale are measures of mental adjustment including emotional reactions as well as coping.