Introduction: Since devolution in 1998, the UK has had four increasingly distinct health systems, in England, Northern Ireland, Scotland and Wales.
Sources of data: Secondary literature and authors' own research since 1998.
Areas of agreement: From a similar starting point, there has been a considerable distancing of the four health systems from each other in policies, priorities and organization.
Areas of controversy: The comparative efficiency and quality of the different systems as well as the wisdom of their greater or lesser reliance on integration and competition.
Growing points: Better and more comparable public data would be useful, as would consideration of potential devolved lessons for UK policy.
Areas timely for developing further research: Comparisons of organization and performance at levels more detailed than whole systems; analysis of the resilience and management of different systems in a context of budgetary austerity; analysis of the politics behind policy decisions.
Keywords: England; NHS; Northern Ireland; Scotland; Wales; policy.
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