On October 6, 1995, the American Society of Maxillofacial Surgeons sponsored a 1-day symposium entitled "Implantable Materials in Facial Aesthetic and Reconstructive Surgery: Biocompatibility and Clinical Applications." The symposium examined issues relating to the biocompatibility and clinical role of alloplastic materials commonly used for facial bone and soft-tissue replacement and augmentation. It provided a forum for the interaction of basic scientists, clinicians, and manufacturers. Clinical and laboratory data concerning a variety of implantable materials were presented and discussed. The program consisted of three parts. The first session was designed to provide historical and scientific background as well as perspective on legal issues surrounding the use of implantable biomaterials. The second session involved the presentation of clinical data on bone and bone substitutes for augmentation of the facial skeleton. The third session was devoted to clinical reports of bone and bone substitutes used for the reconstruction of cranial vault and cranial base skull defects.