a job, and to have a propensity to violence. The second persistent feature is the dismal failure of rehabilitation programmes that aim to diminish the rate at which persistent young offenders commit crimes. Many different approaches have been tried, from intensive supervision to taking young offenders on safaris, but none has worked reliably or effectively. Recent research indicates that a large majority -- perhaps more than three quarters -- of persistent young offenders have brains that have not developed properly. They have, that is, suffered from neglect in the first two years of life, which prevented their brains from growing. As a consequence, they may be incapable of responding to the same incentives and punishments that will steer those with more fully developed brains away from crime. That result may lead you to conclude that nothing can be done about the social problems that result from childhood neglect. But that would be wrong. There is a way to break the cycle, and it is not terribly difficult to achieve. It consists in intervening early and showing mothers who neglect their children how to treat them in a way which will lead their babies' brains to develop fully. "Early intervention", as the policy is called, has been tried in parts of the US for more than 15 years. It consists in ensuring that mothers identified as "at risk" of neglecting their babies are given regular visits (at least once every week) by a nurse who instructs them on how to care