Standard case management strategy has been recommended to reduce the high mortality rate in children with acute respiratory infections (ARI). Appropriate case management has been shown to prevent such deaths, but only if families recognize signs of possible pneumonia and seek care promptly from a trained health worker. The purpose of the present study was to assess mothers' perception and interpretation of ARI signs and symptoms in relation to that of a physician in an urban community in Addis Ababa. Two hundred and twenty-two mothers who brought their children to hospital with cough or difficulty in breathing and an equal number of control mothers were studied. Most mothers did not recognize these signs, including the key signs of pneumonia-rapid breathing and chest indrawing. While it was shown that between two physicians there was good agreement on kappa values above 70% for most ARI signs, there was little agreement between physicians and mothers or between mothers whose children came for ARI problems and mothers of hospital controls. The few mothers who recognized these signs did not interpret them as serious. The study concludes by recommending intensive health education and further ethnographic studies on community beliefs about ARI in children, with particular emphasis on documentation of the terms, signs and symptoms by which families recognize the illness.