We describe 3 young children with Hallermann-Streiff syndrome, 2 with typical manifestations and 1 with the facial changes without the eye abnormalities but with a cleft palate and with complete syndactyly of fingers IV and V. The latter case represents overlap of the Hallermann-Streiff syndrome and oculodentodigital dysplasia. "Dwarfism" as a possible clinical risk marker of mental retardation is discussed. As cause, a mendelian autosomal dominant mutation seems most probable.