Talk to any business in any sector and one of the biggest challenges they face is lack of skills, or more precisely labour. People are in short supply. As a consequence we find ourselves in an economy which for the most part doesn’t suffer from a lack of demand but where growth is primarily constrained by supply.

With record low unemployment attention has turned to other sources of labour. This includes an increasing focus on "labour market inactivity", the more than 700,000 people in Scotland of working age who aren’t working. While this number sounds large it is, at 21%, about the same as the UK level. It comprises early retirees, carers, at-home parent, students and those with ill health and other challenges preventing access to the labour market. The policy mix to address these challenges is wide-ranging, including employability support, training, child care, housing and health interventions. Reducing this inactivity level is the right thing to do for many economic and social reason – including increasing income levels for those individuals and their families – but of itself it won’t solve our labour shortages.

More investment to drive up productivity is required, but again is only part of the answer.

Brexit of course has made the problem worse, and re-accession to the EU single market would be a significant boost to Scotland’s economy. Rising living standards in the EU accession countries and shortages of labour right across Europe, means that the Eastern European labour pool does not, however, have the same potential it once did to single-handedly fill gaps in the Scottish economy even were all restrictions lifted.

Without control over immigration the Scottish Government is anyway limited in what it can do to attract international workers. The Scottish Government’s proposed Talent Attraction and Migration Service can signpost to other services, and serve to draw attention to the damage UK immigration policy is doing to the economy, but it is difficult to see it delivering international labour in the volumes that Scotland’s economy needs.

But there is of course a huge labour pool available to Scotland, closer to home, with no restrictions on its movement or legal ability to work in our businesses and public services.

The "brain drain" is a common refrain, fuelled by historic emigration experiences, and a typically Scottish tendency to underestimate the attractions of living here, but contrary to popular belief, there is an annual net inflow of working-age people to Scotland from the rest of the UK. The average ouflow in each of the last five years has hovered around the 40,000 level, with the annual inflow some 7,000 higher.

So Scotland is already an attractive location for working-age people from the rest of the UK. Income tax differentials over recent years haven’t impacted the willingness of people to move north. (Any future tax changes need, of course, to continue to be carefully assessed for any potential negative impacts.) Considering the total financial picture – including lower cost of housing and council tax, and free services, notably prescription costs and tuition fees – moving to Scotland is still a financially attractive option for many.

Easier commutes to work, more attractive scenery, wider options for recreation and a friendly welcome add to the package.

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The benefits to the Scottish exchequer can also be significant. A 20% increase in the annual number of working-age people moving to Scotland – assuming the bulk are higher rate taxpayers – could deliver an extra £1billion in income tax revenues to spend on Scottish public services over the next five years, not including the economic boost from increased spend in local shops and services.

None of this takes opportunity away from those already living here – quite the opposite. Businesses that can fill skills gaps now, enabling them to grow and export more, will create even more well-paid opportunities for Scottish school leavers in future. We are a long way from running out of highly-paid vacancies to fill.

The Scottish Government’s existing rUK Talent Attraction Group, with business leaders from tech, space, advanced manufacturing and other key sectors, is well placed to advise on the specific actions required. Continuing their work is important.

And this isn’t a choice between an international or rUK focus. Learning what works to make Scotland an even more attractive location within these islands also makes us more attractive to international migrants. It makes Scotland better able to compete successfully in an increasingly competitive European labour market when full immigration powers do come to Holyrood.

The Scottish Government needs to take this seriously and focus on clearly articulating the "move to Scotland" message in the rUK market. Figure out what works, take concrete action to deliver results, drive up the talent pool and the associated tax receipts. Make moving to Scotland an aspiration for those living south of the Border. Fixing our demographic challenges are in our own hands, and we should take responsibility for delivering on that.

Ivan McKee is an MSP and former Minister for Business, Trade, Tourism and Enterprise