The man in charge of setting and marking 11-plus exams for 10 years in Northern Ireland has come out against academic selection.
Dr Alastair Walker, who was head of education services at the Council for the Curriculum, Examinations and Assessment (CCEA) until 2004, has published a book outlining the arguments against selection.
Selection Challenged looks at the last 60 years of education in the north of Ireland and examines research into pupils' academic progress and emotional well-being as a result of selection at 11.
Writing in the Belfast Telegraph, Mr Walker said that grammar schools are currently serving 40 per cent of the community well.
"Transformed into excellent all-ability schools they would serve 100 per cent of our community every bit as well," he said.
Although he is against selection, Mr Walker criticises politicians for getting rid of the 11-plus in 2008 but failing to work together to bring in an alternative system. Schools now administer their own selection tests, but these are not centrally controlled.
"Permitting the chaos of unregulated selection is unacceptable even if it is viewed as a step towards a worthy goal," Mr Walker wrote.
Change in education needs to be very carefully managed, as "mistakes inevitably lead to children being hurt, emotionally or educationally", he wrote. "The present impasse illustrates the point dramatically." mr.