Four children and one spontaneously aborted fetus from 2 separate families have a similar pattern of malformation secondary to duplication of distal 15q. In both families, the abnormal chromosomes were derived from balanced reciprocal translocations carried by the mothers. Clinical features common to the 4 liveborn children include appropriate birth weight, length, and head circumference for gestational age; similar craniofacial anomalies, including sloping forehead, bulbous nose, prominent nasal bridge and septum, midline crease in the lower lip, and micrognathia; arachnodactyly; joint contractures involving hands and feet; cardiac defects; and genital anomalies. The 2 infants with duplication 15q22.1----qter and deletion 13q32.3----qter died in the immediate neonatal period. The abortus, who shared the same chromosome constitution, had an omphalocele and a cephalic defect in neural tube closure. The 2 children with duplication 15q22----qter and deletion 11q25----qter survived but have severe psychomotor retardation and postnatal onset growth deficiency, at 48 and 30 months, respectively. The findings in these 5 cases plus review of the literature permit further delineation of a recognizable pattern of malformation secondary to duplication of distal 15q.