This report describes a family in which two different types of acrocephalosyndactyly (ACS) were clinically identified. The proband presented with the classic stigmata of Pfeiffer syndrome, while her cousin was considered to be a typical case of Apert syndrome. Seven other family members also have unusually shaped heads and the facial appearance reminiscent of Crouzon disease. From the observations made in this family and from previous reports in the literature, we feel there is substantial reason to re-evaluate the ACS classification and to consider that the Apert and Pfeiffer types of ACS may be one and the same.