BBC health correspondent Branwen Jeffreys presents a series of debates as the NHS marks its sixtieth anniversary. In the last decade the NHS in England has used the private sector on an unprecedented scale. Critics claim that private sector involvement drives down standards in a bid to maximise profits, whereas supporters claim that commerical instinct has brought much-needed efficiency, competition and a focus on treating patients as consumers. To what extent should the private sector be involved in the NHS?