Traffic accidents with bicycles are very frequent, since bicycling has become increasingly popular as a means of transportation and a sports instrument. Therefore, there are many bicycling victims in casualty hospitals. The head being exposed and unprotected, head and brain injuries are the most frequent ones. Just as in professional and sports activities, protection of the head and neck also when bicycling has been urgently recommended and ist effect repeatedly confirmed by recent statistical results. Wearing helmets by motorcyclists has clearly reduced the severity and frequency of head injuries since it became compulsory. A legislative initiative for wearing bicycle helmets as well ist therefore necessary.