In addition to detailed observations on four cases of severe infantile hypercalcemia, this paper is of interest because of the special attention to the facial features which have been described as characteristic of the severe form of this disease. Careful consideration of the component parts of the facies is given with the aid of diagrammatic sketches and photographs. A summary of the literature on this subject is provided. The authors doubt the validity of distinguishing between the mild, benign form and the severe form complicated by calcification of the kidneys and mental retardation.