Heads who poach teachers from other schools risk being named and shamed for using underhand hiring methods.
The Secondary Heads Association today launched a code of conduct to stamp out unethical recruitment in schools following complaints from headteachers about colleagues who have lured staff away.
John Dunford, SHA general secretary, said schools had made increasing use of underhand techniques in recent years because of the difficulties they had experienced in finding new teachers.
Although the code of practice cannot be legally enforced, it will be up to local associations to impose sanctions on offenders. This could lead to culprits being shamed or put under pressure to stop underhand approaches.
In one case, a school which sent two teachers on a course later found that they had been recruited by the headteacher who was running the course.
Other heads who have moved to new schools have contacted former colleagues and persuaded them to join them.
Dr Dunford said he recognised that it was sometimes difficult to decide whether a headteacher had acted ethically, but hoped local heads'
associations would still sign up to the voluntary code.
"The poaching of a teacher from another school, without an open advertisement, always causes problems for the other school," he said. "The code of practice is in the interests of individual schools and the wider education system."
The code says that all teaching jobs should be advertised externally, except when it is necessary to recruit from existing staff, and that possible candidates should not be asked to apply until the advert has appeared.
It adds that SHA considers that it is "not good professional practice for a school or college leader to seek to entice a person to leave their post and take up anotheron the basis of private, informal contact".
Other guidelines in the code of practice suggest that:
* schools should not try to outbid each other for candidates.
* heads should not offer salaries above those which are permitted by national regulations.
* applicants should be informed as early as possible about any teaching tasks which they might be asked to perform as part of their job interview, and they are entitled to feedback about their performance and why they were not selected for a job.
* written references should be accurate and, where possible, available to the candidate, and should not differ from spoken references.
Teacher unions have been as critical as headteachers of the recruitment techniques used by some schools.
Doug McAvoy, general secretary of the National Union of Teachers, said that poaching staff was an understandable consequence of teacher shortages but highly unhelpful.
"The schools with the most money are the ones who can afford to poach teachers, so it is the less well-off schools who suffer the most," he said.