SummaryPhonocardiograms recorded in a series of 440 cases of congenital heart disease have been analysed, and the patterns found in the chief conditions described. These patterns are typical in the great majority of cases, and a well‐taken phonocardiogram, while a relatively simple test, will greatly assist in establishing the diagnosis. It may also give a good indication of the severity of the lesion, and of the presence of associated physiological disturbances, such as pulmonary hypertension. Records of diagnostic value may be obtained even in infancy.Phonocardiography serves to make clinical auscultation more precise, so that the maximum amount of information may be obtained from it. It also provides a permanent record of heart sounds and murmurs, which assists in following the progress of patients. It is a valuable adjunct in the study of congenital heart disease.