Prolonged cough is a frequent problem in the community. Several studies in the school setting have found that as many as 4.8% to 10.4% of children suffer from prolonged cough. There is no consensual definition of prolonged cough. In this guideline, we define prolonged cough as a daily cough lasting for more than three weeks. The literature review did not identify any quality study on the aetiology of prolonged cough in children in primary care. A diagnostic decision-tree based on the systematic literature review and expert opinion is proposed. Doctors should seek signs of any serious underlying condition. Chronic productive purulent cough should always be investigated. A careful evaluation of the impact of cough on the quality of life of the child is necessary. In absence of signs of specific underlying illness, coughing is generally a self-limiting condition. Symptomatic treatments have not yet been proven to be effective, and many of them may cause serious side effects. Their use should therefore be limited.