A new points-based immigration system, similar to that in the USA and Australia, has been unveiled by the Home Secretary Charles Clarke.
BBC News website's Dominic Casciani answers your questions about the new system.
Q: I thought they already had a points system: The Highly Skilled Migrant Worker Programme. Has any evaluation system been put in place to test the social integration of these workers?
Stuart, UK
The Highly Skilled Migrant Worker programme, introduced in 2002, was indeed based on points. But it was one of the 80 different ways that people could come to the UK.
Part of the problem with the scheme was that, in the Home Office's own words, some of the ways of earning points were a bit subjective and that meant it wasn't a particularly clear system. The figures bear this out - just over half of applicants for this scheme in 2005 were turned down. The Home Office says its new system is far more straightforward: Has the applicant got a skill? Is that skill in demand? So what they've done is kept the points idea but devised something for all types of workers and students, similar to systems in comparable countries.
As for integration, this is a particularly thorny issue and one that exercises a lot of migrant groups who claim that historically not a lot has been done to help people settle. Some money is being spent on integration of refugees, but this of course, is a different category to economic migration.
Q: What will they do with all the people who are illegally in the country already? Is there a proposal to get them out?
Karla Bee, UK
One of the criticisms of the reforms - from both political opponents of the government and from migrants' rights groups - is that the new system does not answer this question about illegal working (also called irregular or undocumented working).
Experts in the field agree that by its very nature it's impossible to accurately count something that's hidden - so the best they've come up with is an educated guess. The official guess is 570,000 people - but treat that figure with caution. Now, some groups have called for an "amnesty" for these people, arguing that they are working in the black economy, typically in poorly paid jobs like cleaning, agriculture and catering, and by "regularising" them, they can start to pay taxes and so on. Some nations have done this at regular intervals, including Spain and Italy. Others, such as pressure group Migrationwatch UK, says this would reward illegality.
For its part, the government defends the package, saying the flexible points-based system will undermine the pull of illegal working by filling gaps quickly and efficiently.
Q: Will it work? What is to stop people obtaining 'certificates' from some dubious academy and overstating their qualifications? They could then simply enter the country and, if discovered, claim asylum.
Gerry, Merseyside
Immigration systems the world over are notorious to police and many countries that have reformed have found subsequent holes in their policies - indeed a small number of economists argue the best thing to do is scrap any controls and let market forces decide the level of migration the world over.
The new system includes a number of measures that the government says will improve the security and checking side of the equation. Institutions that issue certificates to would-be immigrants, such as students, will need to first be accredited by the Home Office. Secondly, there is going to be a system of financial bonds for people the immigration service thinks may breach their visa.
Q: Why not fill the skills shortage from our own people? If needs be, give them more training. We surely can't keep taking in foreigners?
L Lee, Cardiff
And
Q: Why do we need immigration? Isn't this island crowded enough already. Why don't we put more money and incentives into training our own population?
Neil, Nottingham
Economists have argued long and hard over this point. Some say that the costs of migration outweigh the benefits and question whether or not more should be done to train and equip people to fill gaps in the labour market. Others say that in a markets-driven world, that's not realistic. Take the NHS for example. It has relied on foreign-born and trained workers for decades because it's cheaper for the tax payer than investing heavily in more and more medical schools.
But another issue is that many employers insist that they simply cannot find local people to do the work. Many major agri-businesses, such as the super-farms that supply supermarkets, rely on temporary migrant labour because local people would prefer part-time work all year round, rather than seasonal employment.
Q: I would like to work in the US but I can't being a UK citizen and our applications are already full. So why should it be easy for people from other countries to be allowed to work here?
Jason B, Manchester
Whether or not it will be easy under the new system remains to be seen - but clearly the government's thinking is that it should be easy to apply to come here - but harder to actually get in for those for whom we have no real need. While we don't know how this system will work out, it's very similar to those used by other countries such as Australia.
The reasons why people migrate are complex and varied. Some of those seeking to work in Britain will certainly have very similar aims to Brits who fancy working abroad.
Q: Will this include those who have arranged marriages aboard? Especially cultures which believe in chain marriages ie marrying cousins, etc.
Harjit, Leeds
Marriage is not covered by the points system. Anyone wanting to bring in a spouse has to satisfy other criteria based on family reunion, individual rights and whether or not officials believe it is a genuine relationship. The government has said, however, that it wants to put a stop to "chain-migration" - the process of a relative bringing in another relative - and then that relative applying to bring in another.
Q: Isn't this exactly what the Conservatives proposed in the last election?
Paul, London
The Home Office argues that had been moving towards this system a long time before the general election - and indeed it forms part of the government's five-year-plan announced in February 2005. Some people think however that political pressure led to them getting their faster.
Broadly speaking both parties have argued that there are merits in economic migration - and a lot of policy thinkers in and out of government have been throwing around these ideas for a long time.
The proposals that the Conservatives brought forward at the 2005 General Election were slightly different. They called for a points-based system allied to the idea of annual quotas set by Parliament - and then a separate quota for refugees.
Labour argued that this was not workable. Having said that, the new system will see a Skills Advisory Body come into force, an agency charged with roughly working out how many plumbers or engineers we actually need to plug gaps in the economy.
Q: Who makes the decision as to which field is experiencing a "skills shortage"? Why can't we increase the training for home grown students so there are more doctors, etc?
Raj
The decisions will be based on the advice of something called the Skills Advisory Body - this agency will work with industry and government to try and work out where the gaps are and how quickly to fill them. In effect, what this does is put on a more official footing the kind of negotiations and lobbying that goes on all the time where employers go to the Home Office and appeal to bring in more workers for their particular sector - for instance farmers who like using Eastern European students to pick crops.
Some economists argue that bringing in doctors from abroad may be cheaper for the British tax payer - we don't pay the costs of their tuition - but is creates a "brain drain" in the originating country. The other way of looking at it is that many foreign-born workers send a lot of money home to their families and communities - valuable foreign currency that can make a real difference quickly in the developing world.
Q: I am currently in the UK under the Highly Skilled Migrant Programme. Under the new system, I would not qualify without a job offer. How will these changes be applied to those of us already here under HSMP.
Lynn
We don't yet know with any certainty how the precise mechanics will work on a case-by-case basis but it's perhaps worth looking at some of the things the Home Office are saying for the highly-skilled.
Those who are classed as being the most highly-skilled will be able to come to Britain without having a job offer and have free access to seek work.
In short, the government wants highly-skilled to come to Britain - but says that it won't be a simple case of ranking their qualities, rather "a sophisticated system of weightings and trade-offs".