First, the relationship between post-licence crash risk and the amount of driver training was analysed on the basis of questionnaires from about 30000 drivers who had held a licence between 1 and 18 months. The risk increased with amount of training up to a certain level, before declining. This was explained as due to a discrepancy between the learning curves for subjective and objective driving skills. Second, the optimal amount of driver training was estimated with respect to the total number of crashes during training and the first year after licensing. The optimal level was estimated to be at least 4000 km, which is about twice the present level.