This paper explores the experiences of parents of asthmatic children in the period leading up to their child receiving a formal medical diagnosis. To what extent did the parents face difficulties in obtaining this diagnosis? How did they describe their encounters with the healthcare professionals? In particular, did parents portray themselves as passive and dominated or active and participating during the prediagnosis phase? In-depth interviews with individuals and participants in a focus group exposed the prediagnosis phase as a distinct and memorable phase of the disease, often recalled as a period of frustration and uncertainty. Results show that instead of accepting the authority of the professional, parents eventually acquire knowledge elsewhere about the diagnosis and the healthcare system, and act according to that knowledge. As a fundamental uncertainty appears involved in the diagnostic process, parents dealing with this uncertainty use a number of strategies to gain control of the process of alleviating their child's disease. The paper discusses the status of the information that the researcher obtained from parents. Lay narratives cannot be treated as simple reports of an external reality. As the parental role is rooted in normative conceptions about what constitutes 'responsible parenthood', information given to the observer may therefore be influenced by the informants' concern with their appearance as moral persons or adequate parents. Although a research strategy based on one-sided interviews has limitations, using parents as a source of information offers a rare glimpse into the realities of patient-physician encounters.