It is excellent news: all private colleges that recruit students from overseas will be required to register with the Home Office and prove they are genuine educational establishments. The discovery that hundreds of small language schools in Britain - including some in Scotland exposed in recent weeks by The Herald - have been a front for people to enter the UK to work illegally has raised serious concerns. It is not merely a question of illegal immigration, but the exploitation of genuine would-be students which makes it imperative that these bogus colleges are prevented from perpetrating further abuses.

That new rules will not come into effect until 2009 leaves a worrying window of opportunity for those which are merely an immigration scam to continue to exploit the loophole for the next 17 months. Those that are short-changing students by providing classes which do not meet any recognised standard should be inspected urgently so they can be regulated and, if they meet the criteria, registered. More may be required, such as limitations on the use of the word college, so that it is crystal clear to foreign students who want to study in the UK whether they are applying to a genuine institution.

As The Herald revealed the extent of the situation in Scotland, it became clear the problem is not confined to the 1800 or so colleges that are not on the Home Office register. One in Glasgow, Kelvin Business School, which is under investigation by police and trading standards officers, and believed to have taken tens of thousands of pounds for non-existent courses, was on the official list of providers of education in the UK operated by the Department of Innovation, Universities and Skills. Of two others of doubtful standing recently uncovered by The Herald, one was on the list and the other had applied to join. Given the time-lag between yesterday's announcement and the new registration system coming into effect, it is alarming that Kelvin Business School was still on the register two years after the Association of Scottish Colleges raised concerns about its legitimacy.

It should be remembered that legitimate educational establishments are also harmed by the existence of bogus ones. Overseas students are an increasingly valuable commodity; as Immigration Minister Liam Byrne pointed out, they bring in £5bn a year to the UK.

Further and higher education institutions in Scotland depend on the good name of Scottish education in an increasingly competitive market. Colleges throughout the UK and the Association of Scottish Colleges have been campaigning for tougher regulations. Their concerns should have been addressed sooner. To preserve their high standards and for the sake of all the students working for genuine qualifications, the cheats must be shut down.

As well as an education issue, this is an important immigration one. The student loophole is not only a route for illegal workers to enter the country, but a rather obvious one for potential terrorists. It should be closed before 2009.