This "current controversies" contribution describes the recent case of a severely disabled six year old girl who has been subjected to a range of medical interventions at the request of her parents and with the permission of a hospital clinical ethics committee. The interventions prescribed have become known as "the Ashley treatment" and involve the performance of invasive medical procedures (eg, hysterectomy) and oestrogen treatment. A central aim of the treatment is to restrict the growth of the child and thus make it easier for her parents to care for her at home. The paper below discusses the main objections to the treatment. It concludes that the most serious concern raised by the case is that it may set a worrying precedent if the moral principle employed in justification of the treatment is applied again to endorse it in similar circumstances. Finally, it raises the possibility that that same moral principle may even be invoked to justify more radical interventions than those that were actually performed in the Ashley treatment.