BACKGROUND: Although a personal interview with the patient during the preoperative visit decreases anesthesia-related anxiety, few efforts have been directed at identifying the patients' greatest concerns. The present study was undertaken to assess patients' anxiety regarding anesthetic management and their specific concerns about anesthesia. METHODS: Before any premedication or explanation of proposed anesthetic technique was given, two hundred and ninety five people (family members and patients) scheduled to undergo elective surgical procedures under general or regional anesthesia, were asked the question of what worried them about the anesthesia and what patients really want to know about their anesthesia. RESULTS: The vast majority of patients and their families want to know comprehensive information concerning their general or regional anesthesia including information about all possible complications related to anesthesia. The most common preoperative anxiety and concern regarding the anesthetic procedure relates to complications. In addition, frequent anxiety and curiosity were about recovery time after anesthesia, anesthetic method and pain. Parents and families of children undergoing general anesthesia most worried about brain damage including decline of memory and learning ability. CONCLUSIONS: Reassurance and satisfactory explanations about preanesthetic anxiety and curiosity are required for the patient and their family preoperatively in an attempt to reduce the patient's anxiety.The information from this study could help anesthetists communicate more effectively with the patient and their family during preoperative visits.