A retrospective analysis of all culture-positive cases of Mycobacterium tuberculosis infection in HIV positive individuals, over a 5 year period, revealed 18 cases, drawn from a population of approximately 1500. The prevalence of culture proven M. tuberculosis over the 5 year period was therefore 1.2% and was strongly associated with either a concomitant, or a subsequent, AIDS diagnosis. Sixty-one per cent had pulmonary tuberculosis, 17% had both extra-pulmonary and pulmonary infection and 22% had extra-pulmonary infection alone. Although a wide range of radiological abnormalities was seen, segmental consolidation was the commonest, occurring in 57% of cases. Only 55% of the specimens were positive on initial stains for M. tuberculosis, with a mean duration of 4 weeks to become culture positive, emphasizing that early diagnosis rests on clinical suspicion.