A SHORTAGE of head teachers in some parts of Wales has raised concern.
Local education authorities have had to re-advertise dozens of posts.
The National Association of Head Teachers (NAHT) said it was due to pressure of work and lack of training.
It is more of a problem in Welsh language and faith schools, according to the union.
"It is certainly a concern that is mentioned increasingly by our members, which suggests we are dealing with a more complex problem than previously," said Anna Brychan, of NAHT Cymru.
The Welsh Government said it was aware of a shortage in some areas and that it was keeping an eye on the situation.
BBC Welsh language online news service Newyddion Ar-Lein obtained numbers of re-advertised head teacher posts from 13 out of 22 authorities.
There were 22 in Gwynedd, 19 in Powys and 10 in Pembrokeshire.
Teachers have to complete the National Professional Qualification for Headship (NPQH) before becoming a head.