Kanayo Enwemadu is one of those responsible for the dramatic increase in overseas students studying postgraduate courses at Scottish universities.

The 28-year-old from Nigeria arrived at Glasgow University last September to further her studies in public health after graduating with a pharmacy degree in her homeland.

The reason she came to Glasgow was because Scottish - and UK - institutions have degrees that are recognisable worldwide. "It gives you an edge if you have one," she said.

Ms Enwemadu's choice is good news for Glasgow University in the sense that her fees, and those of others like her, will bolster their finances. She also spends money in the wider economy, which helps Glasgow businesses thrive.

However, like many of her counterparts from across the globe, she wants to return home after qualifying to contribute to the development of her home country.

That leaves Scotland with a problem. While she may return home to tell a positive tale about her time here, which will encourage others to follow in her footsteps, the skills she has learned will not directly benefit Scotland's economy.

That would not be a problem if the rapid rise in overseas postgraduates students in Scotland - up 116% since 2003 - was mirrored by a similar increase in Scottish postgraduate numbers, but it hasn't. Since 2000, the number of Scottish postgraduates has risen more slowly from 13,660 to 15,540.

In addition, proportionately fewer Scottish undergraduates go on to study at postgraduate level than in the rest of the UK, with figures showing that Scotland has only 8% of the UK's postgraduate taught students despite a 12% share of the UK-taught student population.

At the same time, a recent report has highlighted the need for hundreds of thousands of new graduates and postgraduates over the next 10 years to ensure the survival of Scotland's economy.

An analysis of projected workforce trends by Futureskills Scotland, a branch of Scottish Enterprise, concluded the country will need 198,000 additional postgraduates by 2017 and 138,000 extra graduates, to fuel a predicted 18% expansion in professional jobs in the economy.

It is for these reasons that Universities Scotland, which represents university principals, is arguing for a significant increase in funded places for postgraduate students with a £9m injection of funds from the Scottish Government.

"The imbalance should be redressed to enable Scotland to compete. Numbers studying at postgraduate levels have increased very rapidly in the UK and internationally where, in Australia for example, expansion at this level has been considered a priority," said a Universities Scotland spokesman.

"It is crucial that Scotland should compete effectively in this area. Graduates with higher degrees are particularly vital to high-end innovation, which has to be central to Scotland's economic strategy.

"Postgraduate researchers are the group that drives the high-level innovations, which supports the high-quality research base that attracts world-class talent, which fuels collaborative initiatives, and which represents the essential resource for sustaining the current volume and high quality of Scottish university research into the future."

NUS Scotland, however, believes one concern is that Scottish universities don't look after overseas students as well as they could.

James Alexander, president of NUS Scotland, said: "International students are charged a huge amount more in tuition fees than homegrown students, but they often don't get the support they need.

"We have got students who are unable to get a bank account, who are trying to find accommodation from abroad and who are trying to come to terms with a whole different way of working.

"They have much greater support needs than other students, but don't get that from their institutions. If the government wants to see increased numbers of students coming from overseas they are going to have to ensure that the reputation of our education is kept up and a key part of that is the student experience."

But the Universities Scotland spokesman said: "There is no suggestion institutions are taking people for the sake of it because, if they were, the damage done to our reputation would be enormous."