The critical incident technique, is a highly flexible qualitative research method used in solving practical problems. Although this research method has been extensively used in the service industry to evaluate consumers' expectations and perceptions, applications to the study of health care quality are just beginning. This article describes critical incident methodology, reviews previous applications of the technique to the study of health care quality and provides illustrations from research. This practical research methodology offers the following important advantages to those interested in designing studies of care quality: identifying patients' experiences in health care settings, exploring dimensions of nurse-patient interactions and identifying patients' responses to illness and health care treatment.