The purpose of the present study was to reveal possible neurological sequelae of amateur boxing after the introduction of modern medical supervision and safety precautions. Neurological, electroencephalographic and neuropsychological examinations were performed in a total of 53 former champion amateur boxers together with a control group consisting of 53 former football players. The football players were, on an average, better educated than the boxers, but otherwise the two groups were comparable. Complaints, neurological findings and electroencephalographic changes were identical in the boxers and control group. Only minor neuropsychological disturbances were found in the boxers most pronounced in impaired motor function of the left hand. This was further demonstrated by comparing 19 pairs, each consisting of one boxer and one football player, matched according to age, education and vocabulary. No relation between abnormal findings and "occupational exposure" during the boxing career could be demonstrated, not even by comparing three pairs of identical twins, although in each twin of the pairs there was a great difference in the number of fights. This study provides no basis for legislation against amateur boxing at the present time, as it indicates that the existing safety precautions protect the boxers against serious and permanent brain damage.