Further research on biomaterials should permit the development of an adequate microarterial prosthesis. This program should also allow improvements of the presently available arterial substitutes. Various types of conduits have been tested on an experimental model: prosthetic tube, biological conduits either preserved or chemically modified. The most encouraging results have been observed with an arterial conduit, prepared from fresh aorta, treated by trypsin and glycosaminoglycans.