A controlled comparative study was made of the osteogenic properties of various types of bone grafts in dogs. A rating scale was applied to the histological criteria used for the evaluation of the grafts, and a tabular and statistical evaluation of the results was carried out. Fresh autogenous bone was clearly superior; freezedried homogenous bone was the next highest in rating. The rest of the grafts tested rated in the following order: frozen homogenous, decalcified homogenous, frozen irradiated homogenous, freeze-dried irradiated homogenous, fresh homogenous, deproteinized heterogenous, and deproteinized homogenous. An indication of the approximate level of significance of this ranking was given. The deficiencies in the data related to the great variability in the response of the animals and the small numbers of animals at each test interval are discussed.