For the past 3 years, the Committee on Professional Liability of the American Society of Anesthesiologists has been studying records of closed malpractice claims files for anesthesia-related patient injuries. The database of 1004 lawsuits was examined to define the impact of the "standard of care," as judged by a practicing group of anesthesiologists, on the likelihood and amount of financial recovery. We found that payment was made in more than 80% of claims made by patients who were judged to have received substandard anesthetic care. Payment also was made in more than 40% of claims when the anesthesia care was judged to be appropriate. We conclude that in the tort-based system of compensation for anesthesia-related injury, the patient has a high probability of financial recovery for injury caused by substandard care. However, if the anesthesiologist provides appropriate care there is still a greater than 40% chance that payment will be made for the claim of malpractice. (JAMA. 1989;261:1599-1603)