Concepts of personal autonomy and freedom have featured prominently in British social and political history. They are widely regarded as a very positive aspect of British culture. However, the presumption of mental capacity and the privileged status of autonomy over the promotion of well-being may on some occasions result in unnecessary suffering and neglect. Currently, individuals are presumed able to make autonomous decisions about their treatment. Their autonomy can only be challenged through a proactive process, in which the health professional must provide valid arguments for overriding it.