The question of cycle helmets for children should be an easy one for society to decide upon. There is good experimental evidence from case control studies that they help prevent injuries (Thompson, Rivara & Thompson 1989; Spaite et al. 1991; McDermott et al. 1993; Malmaris et al. 1994; Thomas et al. 1994). Commonsense also suggests that they should be effective. So why has there been so much controversy? I suggest that there are three reasons for this. Many cyclists feel that their cycling is part of their personal freedom. They also feel that cycling, with the exercise that it gives, is healthy. Therefore, anything that cyclists see as discouraging people from taking exercise and enjoying personal freedom is wrong. Many cyclists view helmets as a major discouragement to cycling and therefore something to be opposed. There is also the mis-apprehension that each injury needs one preventive solution. Therefore, anyone who is for helmets is against bicycle lanes and separation of bicycles from traffic. This is not the case with other injuries that children receive. For instance, no one would seriously suggest that just because a house has a smoke alarm that there should be no flame-resistant upholstery. Neither would anyone seriously suggest that just because one has traffic calming there should be no additional work carried out against drivers who consume too much alcohol. There is also the mistaken belief that any injury control solution should be completely effective. No one expects seat belts to completely stop injuries to car passengers, so why should be expect helmets to completely prevent cycle injuries. We have personal experience in the difficulties experienced during cycle helmet campaigns in our work in Wales. We used cycle helmets as our first campaign in our Safe Child Penarth initiative (Kemp, Gibbs & Silbert 1994). However, every time we published a piece in the local paper we had letters from Penarth cyclists saying that helmets were unnecessary. These problems were confounded by the publishing during our campaign of the Policy Institute report (Policy Studies Institute 1993). This report, funded by a Cyclists' organization, put all their fears in a form that they could easily use.