Too many headteachers are not placing behaviour high enough on their list of priorities to improve their schools, one of the country's most celebrated heads has claimed.
Sir Michael Wilshaw, principal of Mossbourne Community Academy in Hackney - one of the most deprived boroughs in the country - said heads need to pay more attention to poor behaviour because it is a major contributing factor to teachers leaving the profession.
Sir Michael quoted research by Ipsos Mori which showed that while behaviour was a main concern for parents, it was lower down the list for heads.
"If heads did put behaviour high on their lists, particularly those in tough schools, and dealt with it effectively, (they would see) staff attendance improve, staff turnover also improve and behaviour become less of an issue," he said.
"We must start supporting teachers. People leave the profession not because of extra bureaucracy or a desire to do other things; they leave because of behaviour problems."
Sir Michael was responding to comments made by former behaviour "tsar" Sir Alan Steer in The TES last week, who branded Government plans to scrap the 24-hour notice period for detentions "stupid".
Sir Michael said his school often uses no-notice detentions because giving notice does not act as a deterrent to the most challenging pupils.
"Giving notice to the really hard, the really badly behaved has little effect as they just don't turn up to school. Plus it makes parents take responsibility for their children's behaviour," he added.
Last week, Sir Alan said he had never encountered a problem with giving notice for a detention, and added that a lack of legislation ensuring schools inform parents their child is being detained was "lunacy".
"It is Don Quixote politics," Sir Alan said. "Ministers have invented a problem and now they are charging at it."