We present our first experience with MR in bone grafts in 23 patients. Graft implantation followed curettage of benign bone lesions. The locations were, rather exclusively, the long tubular bones. T1-and T2-weighted spin echo-sequences including intravenous application of Gadolinium-DTPA were performed (Magnetom 63, 1,5 T). A total of 29 examinations (1 follow-up control in 6 pat.) was divided into 5 groups, with regard to different stages after surgery, which varied from 1 week to more than 3 years postoperatively. The MR results were related to the respective groups. The results show typical stages of bone graft incorporation, but also greater individual variations in the duration of incorporation. Our first results, however, represent only "snapshots" of different patients at different stages after bone graft surgery. Therefore some important questions are still unanswered but may perhaps be explained with the help of subsequent prospective studies.