A survey of 26 Czechoslovakian children diagnosed with BCG osteitis during 1981-1986 is presented. Mycobacterial culture was attempted in 19 cases with confirmation of bacillus Calmette-Guerin (BCG) Mycobacterium bovis strain in nine cases. Symptoms appeared approximately 17 months after vaccination; the proximal tibial end, distal femur, and proximal humerus were most affected. Although vaccination has been obligatory since 1953, a different vaccine was introduced in 1980, which led to the diagnosis of BCG osteitis in 1981. The vaccination doses, symptomatology, and methods of treatment are described. The risk of complications and a project for vaccination at later age are discussed.