Inspectors say too many pupils suffer from bullying during their school lives.
A report published today by Estyn also says schools have a responsibility to tackle bullying in all forms under the Education Act 2002, but the ways in which schools deal with bullying varies widely.
'Action on bullying', found that even schools with good strategies to address the problem don't have a common understanding of how important it is to focus on groups of pupils with a higher-than-average risk of being bullied.
They include gay, lesbian and transgender pupils, those with a disability and pupils from a minority ethnic background.
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Crowds came to hear him speak this afternoon in Bangor - a seat where fewer than 100 votes could make the difference at the next election.
Scattered showers with the odd heavy burst possible but there will be plenty of sunny spells too.
A rather wet and windy evening, with rain in the north and showers elsewhere.