The common carotid arteries were anastomosed through a venous graft in a group of ten rats. The right common carotid artery was ligated below and the left above the anastomosis. In a control group both common carotid arteries (CCA) were ligated. While the animals of the experimental group survived without neurological deficit, those in the control group died 2 hours to 11 days after operation. The anastomoses and brains were studied by light microscopy. The model described is convenient for practising microsurgery, and should constitute part of the routine training program of young neurosurgeons.