So are Rory Mackenzie and Judith McClure right ? Does the pay of headteachers act as a deterrent to would-be applicants, as they believe, or are other factors at work? Heads do earn relatively high salaries - up to pound; 76,500 in Scotland, although that pales in comparison with the maximum of pound; 98,000 in England and Wales (outside London).

But a new study on school leadership by the Organisation for Economic Co- operation and Development brings some useful perspective to these issues. It turns out that, of the 22 countries in Europe, Australia and New Zealand which were included in the review, headteachers in Scotland are the second-best paid - next to those in the rest of the UK. Their maximum salaries are more than twice as high as the top of the scale for teachers (in one-third of the countries, the difference is 20 per cent or less). In England, school leaders’ earnings grew by 19 per cent in real terms from 1997-2003, compared to a 12 per cent rise in overall average earnings.

According to the OECD, in countries like the UK where heads are well paid, these statistics should be used to talk up the attractiveness of the job. But the report also recognises that more training and professional development, more varied career opportunities (moving between schools, for example), enhanced autonomy, better support and the creation of leadership teams are crucial in addressing the key complaints heads have - which are about the heavy workload and increased accountability, rather than just salaries.

But it is worth picking up on one of the recommendations in the report: regular monitoring of headteachers’ salaries compared to those in similar grades in the public and private sectors. That might help to keep heads’ pay competitive. Such an exercise would not entirely fix salaries which reflect the extraordinary job heads do. That is why factors other than remuneration are important.