A small number of physicians experience a disproportionate share of malpractice claims and expenses. If malpractice risk is related in large measure to factors such as patient dissatisfaction with interpersonal behaviors, care and treatment, and access, it might be possible to monitor physicians' risk of being sued. To examine the association between physicians' patient complaint records and their risk management experiences. Retrospective longitudinal cohort study of 645 general and specialist physicians in a large US medical group between January 1992 and March 1998, accounting for 2546 physician-years of care. Computerized records of all unsolicited patient complaints were recorded by the medical center's patient affairs office, coded to characterize the nature of the problem and alleged offender, and compared with each physician's risk management records for the same period. Both patient complaints and risk management events were higher for surgeons than nonsurgeons. Specifically, 137 (32%) of the 426 nonsurgeons had at least 1 risk management file compared with nearly two thirds (137 [63%] of 219) of all surgeons (chi2(1)= 54.7, P<.001). Both complaint and risk management data were positively correlated with physicians' volume of clinical activity. Logistic regression revealed that risk management file openings, file openings with expenditures, and lawsuits were significantly related to total numbers of patient complaints, even when data were adjusted for clinical activity. Predictive concordance of specialty group, complaint count, clinical activity, and sex for risk management file openings was 84%; file openings with expenditures, 83%; lawsuits, 81%; and multiple lawsuits, 87%. Unsolicited patient complaints captured and recorded by a medical group are positively associated with physicians' risk management experiences.