Three cases of haemolytic-uraemic syndrome in the Hunter area were reported in February 1995. An investigation was initiated to identify any verocytotoxic Escherichia coli in clinical samples that could be associated with the development of the disease. Escherichia coli O6:H- and O2:H7 were isolated from Case 1. No organisms were identified for Case 2, and Case 3 samples yielded Campylobacter jejuni. In addition, efforts were made to trace sources of any such pathogens in food samples or in the environment generally. Shiga-like toxins were found in meat products sampled from butchers' shops patronised by the families of the three cases. However, it was not found possible to match stool samples with samples of food from sources used by the families of the children. Environmental factors seemed likely to have played a significant role in the development of haemolytic-uraemic syndrome in Case 3. It is suggested that the incidence of the disease may be reduced by increasing the frequency of testing of meat products for Shiga-like toxins I and II and through educational and research programs.