It has been said many times that the NHS is at breaking point. Talk of bed shortages, wasted resources, understaffing and missed targets saturate the media. A Government Adviser has even said recently that hospitals are in a ‘state of war’. High rates of use of agency workers are seen as a symptom of a sick NHS but the reasons for their spiralling use are poorly understood. New research by the National Institute of Economic and Social Research (NIESR) set out to explain why agency workers seem to be keeping the NHS alive. The research diagnoses the root causes of high agency spending, revealing that agency working is only the symptom of a much larger, chronic problem around NHS staffing.