And the consequence is...
The average number of applicants fell by about two between 2000 and 2002, judging by analysis of nearly 8,000 school questionnaires issued for the two major headteachers' associations.
During the past school year few primary leadership posts attracted more than six applicants. The smallest rural primaries and small urban infant schools averaged four applicants and even larger schools averaged only seven.
In secondaries, the decline has been even more marked. Group 5 and 6 schools have seen applications drop from an average of 24 in 2000 to between 15 and 17 in 2002.
Adverts for deputies are also attracting less interest.
Generally, schools in London attract below-average numbers, as do many Roman Catholic schools. Although comparative data for special schools is not available, they too attracted very few applicants for heads' or deputies' posts last year.
Apart from the workload problems, the decline may be due to the age profile of the profession. Department for Education and Skills figures show that there were only 4,000 deputy heads in primaries aged 35 to 45 in 2001. As around 50 per cent of new heads are drawn from this age bracket, this leaves little choice for the 1,500 posts filled each year by first-time primary school heads.
In secondaries, the choice is somewhat better, as there are fewer schools and more staff to select from, as most secondaries employ more than one deputy. The Government's insistence that all candidates should either hold - or be studying for - the National Professional Qualification for Headship from 2004 may have little effect on applications at secondary level but might do so at primary.
Special schools may struggle to find candidates with the NPQH and a specialist teaching background. Add to this the complications of meeting staffing needs in specific regions and denominations and market pressures, and it becomes evident that the National College for School Leadership's task is daunting, if not Herculean.
John Howson is director of Education Data Surveys. firstname.lastname@example.org