We have reviewed the incidence of bacteriologically or radiologically confirmed acute haematogenous osteomyelitis in children under 13 years of age resident in the area of the Greater Glasgow Health Board between 1990 and 1997. In this period there was a fall of 44% in the incidence of both acute and subacute osteomyelitis, mainly involving the acute form (p = 0.005). This mirrors the decline of just over 50% previously reported in the same population between 1970 and 1990. Using multiple regression analysis a decline in incidence of 0.185 cases per 100 000 population per year was calculated for the 28-year period (p < 0.001).Staphylococcus was the most commonly isolated pathogen (70%). Only 20% of patients required surgery and there was a low rate of complications (10%). In general, patients with a subacute presentation followed a benign course and there were no complications or long-term sequelae in this group.Haematogenous osteomyelitis in children in this area is becoming a rare disease with an annual incidence of 2.9 new cases per 100 000 population per year. Our aim was to assess the changing epidemiology of acute and subacute osteomyelitis in a single health district from 1990 to 1997, with particular reference to the incidence and the type (acute or subacute) and site of presentation. In addition, we assessed and compared the pathogens responsible, the routes and duration of antibiotic therapy, the need for surgery and the complications encountered with those of earlier series.