The accepted wisdom is that addiction to drugs, like ice or heroin, is a disease of the brain. Neuroscientists can actually see how drug use alters the brain. Drug users, therefore, should not be blamed for their addiction: they are not weak, or bad, or morally flawed. Because their addiction a disease, it follows their condition should be medicalized and treated by clinicians. This, so called, 'brain disease model' of addiction is now being seriously questioned. Paul Barclay talks to some of dissenters.