The authors present a review on the incidence of osseous complications after calmettization with the Soviet BCG vaccine during the period from February 1, 1980 and June 30, 1985 when the total dose of the vaccine was used, as compared with the period from July 1, 1985 to December 31, 1989 when the dose of the vaccine was reduced to half. During the first period 28 cases of the disease were recorded (on average 5 cases in every year of birth) which was an incidence of 3.71/100,000 vaccinated children. After reduction of the vaccine dose to half another 11 cases of the disease were recorded, i.e. a reduction of the incidence to 2.30/100,000 vaccinated children. During the last two years of this period only one case in each vaccinated birth year was notified. A major part of the children with bone complications after calmettization was vaccinated with a batch of vaccine which contained a higher number of germs, close to the upper range of normal values. In the development of these complications thus, no doubt, among other factors also the dose of vaccine participates. As bone complications occur after calmettization even after reduction of the dose of vaccine to half, though the incidence was lower, is should be considered whether the hitherto used dose used for vaccination of neonates is not too high.