Leader: Too many eggs in a fragile basket

British universities are becoming increasingly dependent on overseas students' fees - dangerously so, many good judges believe. Jonathan Nicholls, the registrar of Birmingham University, cites one hard-pressed institution that is relying entirely on growth in overseas recruitment to clear a £6 million deficit. Others in less straitened circumstances are rebalancing their intakes to maximise income and invest in other areas. Events beyond the control of any academic planner - such as a shift of policy in China or an avian flu pandemic that restricts foreign travel - would devastate parts of the UK higher education system. The flutuations in Australian universities' recruitment have shown the impact of even relatively minor changes in study patterns when the reliance on overseas students is too great.

For the moment, however, institutions are certainly not discouraged from expanding their foreign ventures. Rather the reverse: the Government is urging universities to raise more of their own money, and this is one obvious route. Ministers take part in recruitment missions and endorse reports that forecast continuing rapid growth in demand for UK higher education. So where is the fabled "joined-up thinking" in the series of visa obstacles that have been placed in prospective students' way? Just as two hikes in visa charges are shown to have the damaging impact that was widely predicted, the Home Office proposes to withdraw the right of appeal from those whose applications are rejected (page 1). Quite apart from the denial of natural justice that such a move would represent, this would be a classic own goal in a strongly competitive global education market.

If UK universities are to safeguard their positions as destinations of choice for students from all parts of the world, they need help from the Government and constructive thinking of the type that the Higher Education Academy engaged in last week. Recasting courses for an international intake is a delicate business that carries inherent dangers of its own: there is a limit to the cultural dilution that can take place before the focus of a programme is lost. But additional help - both academic and social - has to be available to overseas students if they are to be attracted in the numbers that universities need. UK universities have benefited from visa restrictions in the US and a preference for shorter British courses. But the good times are not guaranteed to last.