Thirteen patients with nasomaxillo-acrodysostosis are described. Some have the facial appearance of this syndrome only, although the others are more severely affected, with skull, eyes, ears, vertebrae and peripheral extremity involvement. The features of the 13 patients were studied and compared with those described in the literature as belonging to 'maxillonasal dysostosis' and 'acrodysostosis'. It seems certain that there is in fact only one syndrome, which differs only in extent of involvement.