(1) New data on adverse events potentially linked to vaccination against hepatitis B in France were made public in October 1998. (2) The incidence of spontaneous notifications of new cases of central demyelination during the period 1990-1997 was about 1 case per 100,000 hepatitis B vaccinees. (3) Preliminary results of two case-control studies show no statistically significant increase in the risk of central demyelination after hepatitis B vaccination. (4) A risk of neurological complications linked to vaccination against hepatitis B cannot be ruled out, but, at worst, must be very small.