Autogenous bone is regarded as the gold standard for bone graft materials as it provides 3 elements necessary to generate and maintain bone: scaffolding for osteoconduction, growth factors for osteoinduction, and progenitor cells for osteogenesis. Allograft is more limited than autograft in these essential elements and yields more variable clinical results. Composite synthetic grafts offer an alternative that can potentially unite the 3 salient bone-forming properties in more controlled and effective combinations than can be obtained in many clinical situations, without the disadvantages found with autograft. This article examines the underemphasized but crucial role of the osteoconductive scaffold in the composite synthetic bone graft.