Basal cell carcinoma of the skin is the commonest form of cancer in the white population. A simple pathological classification is presented and recommended for general use to aid clinicians in their management of cases. Basal cell carcinoma can be classified as nodular, infiltrative, superficial apparently multifocal and mixed in terms of the histological growth pattern. These patterns can be related to the likelihood of complete excision and, if excision is incomplete, to the frequency of recurrence.