Few topics inspire more heat and less light than integration. A debate on the topic can cover all manner of subjects including demographic change, social relationships across ethnic boundaries, the interaction between race and social class, and questions of national identity and cultural adherence. As a consequence, integration has the distinction of being a public policy question which can become less intelligible the more it is aired. But these questions aren’t mere debating points: they have huge potential societal impact.

As this collection reveals, there is a great deal of data out there on the British integration story, and it shows a varied picture. On the one hand there is a story of declining discrimination, an increase in mixed race children, upwardly mobile minorities and unselfconsciously mixed suburbs. But elsewhere there is also a story of parallel lives and what Robert Putnam has called ‘hunkering down’. The real concern about segregation is two-fold. First, is it likely to undermine social peace and solidarity? And second, will it deprive any group of opportunity, or reduce their life chances?

Our contributors offer some suggestions. And while it’s too early to draw too many conclusions, what they say challenges us to look afresh at the question of ethnic diversity and its impact on our wellbeing. For this reason, this collection marks the launch of the Demos Mapping Integration project, which will have the Integration Hub website at its heart. This will, when completed, pull together existing data held by government, academic and private sector organisations to offer a user-friendly, authoritative and politically neutral overview of our understanding of these complex matters. In so doing, it hopes to close the gap between the ordinary voter and policymakers on a vital but sensitive subject.