Acute respiratory infections (ARI) are among the principal causes of mortality of children under 5 years of age. Most deaths are due to pneumonia, which, when timely identified and properly treated, could be avoided. An effective case management scheme, based on early recognition of pneumonia and prompt antibiotic treatment, relies on early recognition of alarm signs by mothers and community health workers. For mothers to understand and act on advice from health workers, language and concepts commonly used by mothers should be utilized. The present study was carried out to compare the relative effectiveness of two different methods to elicit local terms used by mothers to refer to ARI symptoms/signs/treatments. A comparison was made among the terms elicited by a free listing of common terms mentioned by mothers in relation to ARI, and the terms they recognized when looking at a video that showed children with different ARI signs. The video was shown in a community and a clinical setting, in order to identify strengths and weaknesses of showing it in these settings. The video elicited more signs dealing with serious illness, respiratory distress and general malaise, but missed non-visual signs, such as fever, lack of appetite or pain. Also, mothers tended to be distracted by trivial signs, such as skin color. Free listing was easier to administer and elicited more non-life-threatening symptoms/signs, but mothers were more prone to drift away and mention terms not related to respiratory illness. Showing the video in the clinic elicited more medical-related terms, and was easier to show than in the community. In conclusion, choice of either of the two methods depends on the researcher's purpose. Using both methods produced a larger list of terms associated with ARI.