The diagnostic criteria and management strategy of transient ischemic attack (TIA) have drastically changed for these years. In Europe and the United States, community and hospital-based studies demonstrated a higher risk of stroke immediately after a TIA than previously considered. Urgent evaluation and immediate initiation of treatment reduces stroke after a TIA dramatically. We establish the Japan TIA research group, which is subsidized by the Ministry of Health, Labour, and Welfare, Japan. The group conducted a nation-wide survey using a questionnaire and a retrospective registration study to clarify the current status of clinical practice of TIA in our country. We are also preparing a prospective, nation-wide, multicenter registration study of TIA patients. These topics were reviewed in this symposium.