By Dominic Casciani
BBC News community affairs
What do we know about immigration to Britain?
Eastern European workers looking at job ads in a London shop
For the past few years there has been a growing political and public clamour over migration which reached a height at the 2005 general election.
But throughout all of this time, there has been a great deal of dispute about what has actually been happening in Britain - and whether or not it is something to really worry about.
With the publication of the BBC's Born Abroad project, we can try to answer far more of these difficult questions than ever before - although we make no claims that we are revealing all the answers.
Born Abroad is drawn on data processed by an expert team at Sheffield University for the Institute for Public Policy Research, a think tank.
The BBC news website has taken all of this data and turned it into a website for the public to see what was happening locally in their area at the time of the 2001 Census.
Naturally the world moves on and there have been significant changes since then. Asylum numbers have rapidly changed (up and then down again), new workers from Eastern Europe are arriving thanks to EU enlargement, there are controversies over illegal immigrants and also moves by government to restructure economic migration from top to bottom.
But putting these issues aside, the data reveals some important points about what makes up modern Britain.
Of the total foreign-born population of Britain - some 4.3m people - recent immigrants today make up just over half of the total. This shows beyond a doubt that the UK is one of the principal industrialised nations in a complex picture of international economic movements.
With new immigrants tending to be younger and from a more diverse background, the figures show how migration has increasingly been on economic grounds alone. This marks a change from past decades when migration tended to be on family grounds - the arrival of a spouse, for instance.
Asylum: Migration debate has focused on a few key issues
Immigration is overwhelmingly the story of London's development - four out of 10 people born abroad have their home in the capital.
They make up about a quarter of London's population: An almost uncountable range of peoples has arrived in the capital over the years, making up a remarkably broad patchwork of nationalities, ethnicities, languages, communities and identities.
All of this cements London's international reputation as a leading "world city" - a place that seems to become home to anyone from anywhere.
But while immigration is predominantly a London story, migration is now affecting almost every area of the country in ways that have not been seen before.
Take the North East for example. It has the lowest number of people born abroad living there - but has experienced the second fastest rate of change. Taken together with north-west England, the two regions would have experienced significant population declines without the current rate of immigration.
It is this rate of change, some of it quite sudden in some areas, that raises important questions about how Britain as a nation has been able to handle this change.
Have people been prepared for it? Are those who arrive helped to integrate and play a full part in society?
Historically, immigrants have been largely taken to mean people born in Ireland, India, Pakistan, the Caribbean and so on. But this is no longer the case.
The new economic migration, couple with the now declining numbers of asylum seekers, has brought with it a far wider range of nationalities than those typically part of popular memory.
Foreign workers: Increasingly a sight in agriculture
Some from each of these groups - people from Brazil or parts of Africa outside the Commonwealth for instance - will certainly spend the rest of their lives in Britain.
So while the debate over integration has for years generally focused on a few ethnicities and their needs, the reality is far more complex.
The local detail
Where Born Abroad differs from every other attempt to understand migration is the level of local detail that the BBC has been able to provide people.
For the first time, people will be able to find out easily how migration has played a role in their neighb
In many respects - and for many people who come to these pages - it may be a case of stating the obvious.
So people in Grimsby will not be surprised to see the town includes people born in Norway and Denmark - former fishermen who came to the town when it was an important port and stayed on through love and marriage.
But understanding how these local stories fit into a national picture - and assessing the face of modern Britain - has never been possible before now.
The issues raised by the data in Born Abroad are a key part of British public life - not least the wide and contradictory nature of how well people actually do.
Without a doubt, the conclusions each of us personally form on immigration will play a crucial role in how Britain will look and behave in the years to come.