With NHS England and NHS Improvement now a single entity, having seven regional teams to carry out work on the ground, what can be learned from previous incarnations of the NHS that relied on regional bodies? A new Nuffield Trust report by Nigel Edwards and Helen Buckingham (with support from Professor Sally Sheard and Dr Philip Begley at the University of Liverpool) asks the people who were there to provide some much-needed lessons from recent history to apply to the present day.