The objective of this chapter is to introduce the bone grafting and bone substitutes. The science, technology and clinical applications of bone grafting have advanced remarkably over the last 20 years. Skeletal defects can be repaired using a variety of different types of graft, each having relative advantages and disadvantages for any specific reconstructive surgery. The present techniques of bone grafting, there are relatively good indications for all forms and types of grafts but these indications are changing as further advances are made. The focus of this chapter is on the current status of bone grafting with an emphasis on the selection of specific graft materials. There are numerous ways to classify bone grafts. Grafts can be distinguished as to their source (autograft, allograft or xenograft), bony architecture and structure (cancellous, cortical, or corticocancellous), site of origin (local or distant), blood supply bone grafting and bone substitutes, (nonvascularized or vascularized), or their preservation method (fresh, frozen, freeze-dried, or demineralized) are described briefly in this chapter.