The frontozygomatic suture of human cadaver material was examined by a combination of histologic, radiographic, and gross tecniques to determine the aging changes in the suture and the approximate age at which sutural fusion occurs. The sample consisted of sixty-One specimens of human beings ranging in age from 20 to 95 years. Observations were made on specimens at age intervals of 5 years. Since the frontozygomatic suture is bilateral, one suture from each specimens was used for radiographic and gross examination for synostosis, and the opposite side was subjected to histologic analysis. The findings of this study have lead to the following conclusions: 1. The human frontozygomatic suture undergoes synostosis during the eigth decade of life, but does not completely fuse by the age of 95 years. 2. Synostosis is a progressive process which commences as small areas of bony union that occur initially within the internal portion of the suture and then progresses to the orbital perisosteal surface. Bony union is not found at or near the facial periosteal surface. 3. The bony surfaces of the frontozygomatic suture become increasingly irregular with advancing age as a result of the formation of projections or interifitations=