We report a prospective study of travel-associated illnesses observed after their return in 109 French travellers, including 86 tourists. Sixty-three were returning from Africa and 84 percent had been abroad for less than 4 weeks. The percentages of travellers immunized against tetanus, poliomyelitis and typhoid fever were 70, 63 and 36 percent respectively. Malaria prophylaxis was well adjusted to current recommendations in only 19 patients; for 9 patients it was a routine visit. One hundred patients reported 105 diseases. The diagnosis was undetermined in 31 patients, including 19 with diarrhoea and 8 with fever, and it was determined in 74 patients who were found to have malaria (14), cutaneous myiasis (12) or bacterial skin infections (12).