Travellers' diarrhoea represents the most frequent health problem when travelling in developing countries. In most cases it is a self-limited disease. Nonetheless it can cause incapacitation and significant morbidity. It can become persistent in up to 3% of travellers who have suffered from acute diarrhoea in regions at high risk. This article discusses the investigations and the management of diarrhoea in returning travellers, preventive measures and its management during travel.