The Dyggve-Melchior-Clausen syndrome is inherited in an autosomal recessive mode and is clinically characterized by mental retardation, small stature mainly due to a short vertebral column with thoracal kyphosis, protruding sternum, reduced articular mobility, and in most cases also by microcephaly. Specific radiologic findings concern the vertebral column, the pelvis, and the hands. A patient suffering from this syndrome is presented, the literature is summarized, and the clinical and radiologic manifestations are reviewed. As in two cases studied by others [27], the incorporation of radioactive sulphate into the mucopolysaccharides of the fibroblasts was normal in our patient. The activity of arylsulphatase B in the fibroblasts, however, was reduced as in the leucocytes of three reported cases [21]. These observations suggest that an as yet undefined specific sulphatase could be of importance for the pathogenesis of this condition.