Heads are being "blackmailed" by newly-qualified teachers who are exploiting schools' recruitment problems to gain extra cash and perks.
Anne Welsh, Secondary Heads Association president, will say today that recruiting teachers at any level remains a "huge, time-consuming challenge for us".
She is due to tell the SHA conference in Harrogate: "Increasingly, even in the North-east, newly-qualified teachers in all subject areas are playing us against each other to demand the highest possible starting salary as well as perks."
The head of George Stephenson high, Newcastle, told The TES she had recently had to withdraw a job offer from a newly-qualified history teacher. He had demanded a management allowance, which is not supposed to be given to NQTs, and a laptop. History was not even a shortage subject, she said.
Ms Welsh will also warn her members that excessive workload is threatening to worsen a shortage of school leaders and middle managers, with another 250,000 needed in the next decade. She had advertised three such posts in January and had only managed to appoint one without re-advertising.
She will also warn ministers and government officials that the joint working with health and social services envisaged under the new Children Bill will have to be carefully worked out.
Ms Welsh is used to liaising with professionals from other disciplines, having had a full-time psychiatric nurse in school since 2000. The scheme began when it was discovered that her school, which serves several large council estates on the edge of the city, had more pupils with mental health problems than others in the area.
She believes the approach has worked well but only because she has had the time to develop it properly and find a nurse able to work with groups of pupils.
She will say: "Working with other professionals in schools is not always straightforward as we have discovered recently in trying to put together a multi-agency team for our behaviour improvement plan.
"It has taken many months because of the different professional values, working practices and working relationships of the various partners."