Multilateral collaboration as a basis for the future organisation of paediatric services? The NHS plan1 opened by affirming the value placed on the NHS, while also casting a warning shadow: “The NHS is the public service most valued by British people . . . In an age when our lives and jobs are undergoing constant change, it is reassuring to know that the NHS is there and will take care of us in times of need . . . Yet, despite its many achievements, the NHS has failed to keep pace with changes in our society . . .” Recent experience in the NHS has been of radical organisational change: acute trust mergers; the formation of primary care groups and primary care trusts; changes in commissioning arrangements. As policies set out in the NHS plan are translated into practical effect, changes to the structure and functions of NHS organisations are continuing apace. But the organisation of health service delivery is also changing, with improved access to care, clinical outcome, and patient experience of care as primary objectives.2 Within secondary health care in particular, one powerful tendency has been a movement toward subspecialisation in medicine, backed up by evidence that access to specialist opinion and skills improves quality of clinical outcome.3,4 Specialisation of function and concentration of activity tend, together, to indicate a centralisation of services, but the scale at which it becomes viable to provide specialist services varies. The redesign of organisations and services is made less sure because of a lack of relevant evidence5 or because evidence is inconclusive.6,7 As Smith8 reports “ . . .it doesn't make sense for hospitals serving 150,000 to try to provide all acute services . . . The surgeons are keen on hospitals that serve …