The importance of the therapeutic time window for ischemic stroke has been widely accepted for a long time. Consequently, I have been thinking about the past, when the term "brain attack, " which was reimported from the United States, began to spread by repetition. In the 1980s, I had made an enthusiastic study of acute-phase cerebral revascularization for ischemic stroke. At that time, we could cure only a quite lim­ ited number of patients, such as those who already were hospitalized or who, fortu­ nately, were brought to the hospital within a few hours from the onset of the stroke. RM Crowell, in his 1977 report! on cases of failure, had identified the consider­ able problems in acute-phase cerebral revascularization as diagnosis of tissue reversibility, brain-protective reagents or methods, and effective techniques for revascularization. I remember that we strongly endorsed his opinion. Recently, the basic study of stroke has advanced significantly, resulting in newly developed materials and new experimental techniques, which are introduced in this book. I hope that new basic knowledge will be clinically applied.