Cycling is a healthy activity for children, but accidents do occur and can result in death or disability. In the UK, around 28 children per year die from cycle injuries and most of these are directly attributable to head injury, and figures for permanent brain injury are around 1,000 children a year. What are the potential benefits of legislation on helmet usage and reduction in injury? Early studies from 1996 showed that helmets reduced the risk of severe brain injury by 74%. Subsequent studies in other countries have confirmed these initial findings, and a meta-analysis using 16 studies by Attewell in 2001 showed clear benefits of helmets in reducing injury including when there has been a motor vehicle impac; a situation that is more likely to lead to serious injury than a fall from a bike. Furthermore, upper and mid facial injuries are reduced by helmet usage and Thompson et al. have demonstrated a protective effect of 65%. Legislation for compulsory wearing of cycle helmets has been introduced in many countries including over one-third of States in USA, with significant reductions in head injury rates and deaths. Initial concerns about a reduction of cycling activity have not been confirmed. There is a good case for continued introduction of legislation to maximise helmet wearing by young cyclists.