In the 16-year period 1975-90, there were 267 cases of acute infection with typhoidal salmonellae reported in Scotland, in addition to which 32 chronic carriers were identified. The overall incidence of disease changed little over this period, but there was a fall in indigenously acquired paratyphoid B and typhoid, and a rise in imported paratyphoid A. The majority, 215 (81%), had a history of recent travel and were considered to have acquired infection overseas. Only six of the indigenously acquired infections were traced to acutely infected persons, illustrating the low risk of transmission associated with acute enteric fever in the UK. Only one death was definitely ascribed to enteric fever, and one person with S. paratyphi B became a chronic carrier. Significant illness was observed in five chronically infected individuals, including one with carcinoma of the gallbladder. UK residents of 'Asian' ethnicity returning from the Indian subcontinent accounted for 63 (46%) of the 137 cases of typhoid, and 34 (64%) of the 53 cases of paratyphoid A. People of 'Asian' ethnicity were more likely to have acquired infection overseas than 'non-Asians': 110 (89%) of 123 persons compared with 105 (73%) of 144 (odds ratio 3.1, 95% confidence interval 1.5-6.6, P = 0.001). Although there seems to be limited scope for preventing indigenously acquired infection, immunisation of travellers could contribute significantly to reducing the incidence of typhoid.