For months now Brexiteers have been calling for the UK to adopt an Australian- style points-based system. It sounds robust and meritocratic. You can see why it is a compelling line for any politician to trot out.
The problem, as we learned over the weekend, is that the Prime Minister doesn't agree. Theresa May told an audience in China that "what the British people voted for on 23 June was to bring some control into the movement of people from the European Union to the UK. A points-based system does not give you that control."
May is speaking from experience. The UK had a points-based system when she became Home Secretary in 2010 and she set about dismantling it.
It was introduced by the last Labour government in 2008, under the direction of then Immigration Minister Liam Byrne. Byrne didn't pull the idea out of thin air; in 2007 he told an audience in Sydney that "a new Australian-style points-based system will be simpler, clearer and easier to enforce. Crucially it will give us the best way of letting in only those people who have something to offer Britain."
Over time, the UK's points-based system has been scaled back, whether to reduce migrant numbers or prevent abuse. That scaling back began as early as 2009 but really took off under May's leadership as Home Secretary. Most of the Australian features that the system employed have now been removed.
Like the Australian model, our system was designed to allow talented migrants from outside of Europe to come to the UK and find work. Highly skilled migrants were awarded points for a variety of attributes and could trade one characteristic off against another - a young well qualified person might get a visa despite having a low salary, a very well paid person might qualify despite having no academic qualifications or being a little older. English language was a must, as was a moderate amount of savings to pay for food and accommodation when you arrived.
In many respects the policy worked well. It was a useful way in to the country for well qualified bright young things, whether to join our workforce or create their own businesses.
But the policy was far from perfect. Home Office research suggested that 30% of people awarded the visa were either not working in skilled jobs or were unemployed. May responded by closing down the route, only allowing entry where a skilled migrant had a job offer from a company willing to provide sponsorship and monitor their immigration status.
This, I suspect, is where her thinking is now. Brexit might mean an end to the free movement of EU nationals but British businesses will still need to access their skills. Having ruled out a points-based system, I can only assume that the Prime Minister wants to extend the existing demand driven immigration system to EU nationals. They can come over if their skills are needed for a particular job, but not to simply look for work. Otherwise, what would be the difference?
There would need to be changes. Right now our work visas are only available to people filling graduate level jobs. That won't help the sectors that have become increasingly reliant on workers from the continent since the EU expanded in 2004, for instance catering and farming. Ultimately the government should do more to get British people working in those sectors but it won't happen overnight.
This is not to say that there are no lessons to be learned from the Australian system. It is well understood that the Scottish government, for instance, has demographic challenges and wants free movement to continue.
The Australians allow state and territory governments to nominate and sponsor migrants with the skills they need. Why not give a quota of visas to the Scottish government, and for that matter local governments elsewhere in the UK, and let them do the same?
This needn't be an open door policy. For Australia it isn't enough to be good at what you do. You need to be better than the rest. Visa applicants are sifted and grouped by occupation, with a ceiling on the number of visas available for each job. They are then ranked automatically based on the self-assessed scores and prospective migrants with higher rankings are invited ahead of other prospective migrants.
So, is May right to entirely rule out an Australian-style points-based system? You can see why she wouldn't rush to endorse a policy that didn't work perfectly last time round.
Ultimately though the UK needs a system that helps business get the skills they need without undermining British workers. If an Australian system isn't the answer, we need to know what is and soon. Brexit was always going to create uncertainty, but that uncertainty will not help businesses who need to plan and nor will it shut up the Brexiteers who will continue to insist that an Australian points-based system is the only answer.