This study investigates the relationship of resorptive and depository surfaces to the maintenance of bone graft volume in the growing rabbit facial skeleton. Bone grafts fare best (1) when their periosteal surface is placed in contact with soft tissue and their cancellous surface in contact with bone and (2) when bone is grafted to periosteal depository recipient sites. Fluorescent microscopy failed to demonstrate any difference in the rates of calcification in any of the grafts studied.