BackgroundOver the life of the NHS, hospital services have been subject to continued reconfiguration. Yet it is rare for the reconfiguration of clinical services to be evaluated, leaving a deficit in the evidence to guide local reconfiguration of services.ObjectivesThe objectives of this research are to determine the current pressures for reconfiguration within the NHS in England and the solutions proposed. We also investigate the quality of evidence used in making the case for change, any key evidence gaps, and the opportunities to strengthen the clinical case for change and how it is made.MethodsWe have drawn on two key sources of evidence. First, we reviewed the reports produced by the National Clinical Advisory Team (NCAT) documenting its reviews of reconfiguration proposals. An in-depth multilevel qualitative analysis was conducted of 123 NCAT reviews published between 2007 and 2012. Second, we carried out a search and synthesis of the literature to identify the key evidence available to support reconfiguration decisions. The findings from this literature search were integrated with the analysis of the reviews to develop a narrative for each specialty and the process of reconfiguration as a whole.ResultsThe evidence from the NCAT reviews shows significant pressure to reconfigure services within the NHS in England. We found that the majority of reconfiguration proposals are driving an increasing concentration of hospital services, with some accompanying decentralisation and, for some specialist services, the development of supporting clinical networks. The primary drivers of reconfiguration have been workforce (in particular the medical workforce) and finance. Improving outcomes and safety issues have been subsidiary drivers, though many make the link between staffing and clinical safety. Policy has also been a notable driver. Access has been notable by its absence as a driver. Despite significant pressures to reconfigure services, many proposals fail to be implemented owing to public and/or clinical opposition. We found strong evidence that some specialist service reconfiguration including vascular surgery and major trauma can significantly improve clinical outcomes. However, there are notable evidence gaps. The most significant is the absence of evidence that service reconfiguration can deliver significant savings. There is also an absence of evidence about safe staffing models and the interplay between staff numbers, skill mix and outcomes. We found that the advice provided by the NCAT reflects the current evidence, but one of the NCAT’s most valuable contributions has been to encourage greater clinical engagement in service change.ConclusionsThe NHS is continuing to concentrate many district general hospital services to resolve financial and workforce pressures. However, many proposals are not implemented owing to public opposition. We also found no evidence to suggest that this will deliver the savings anticipated. There is a significant gap in the evidence about safe staffing models and the appropriate balance of junior and senior medical as well as other clinical staff. There is an urgent need to carry out research that will help to fill the current evidence gap. There is also a need to retain some national clinical expertise to work alongside Clinical Senates in supporting local service reconfiguration.FundingThe National Institute for Health Research Health Services and Delivery Research programme.