A modification of the previous methods of producing cerebral ischaemia in rats (Koizumi et al., Longa et al.), using an intraluminal thread technique, is described. The middle cerebral artery is occluded by introducing a simple 3-0 nylon thread (0.20-0.249 mm in diameter) through the internal carotid artery in the neck. It has been proven that with this method reproducible focal cerebral ischaemia can be achieved which resembles human stroke. Therefore this simple and relatively non-invasive model is suitable for the pathophysiological investigation of ischaemic stroke and the testing of potential therapies.