Complexity and health – yesterday's traditions, tomorrow's future

'If it is complex it means we don’t really understand it, and the way forward is to break the problem down into its parts to make sense of it'. This thought reflects the way we have been taught, and the way we largely practise in clinical care every day.But are we really functioning on this basis? Or is it the only way we know how to live? We all experience situations every day where the evidence does not really fit our understanding of a problem – the familiar reductionist approach limits our ability to fully explore new problems and to gain new insight. An increasingly persistent question has emerged in relation to what constitutes the knowledge we need for effective and efficient clinical care, an issue taken up by this new Forum on Systems and Complexity in Medicine and Healthcare