Wales has seen a sharp increase in the number of children worried about bullying, a charity says.
One-in-four calls to ChildLine said they were being bullied
ChildLine Cymru said it has been contacted by almost 4,500 young people this year - compared to just under 3,000 in 2003.
The charity said bullying is the single biggest reason why children phone its special helpline and now accounts for one in four calls.
Most of the youngsters ringing in were aged in their early teens.
The ChildLine Cymru/Wales figures show a rise in the number of calls by more than 60%.
The charity's counsellors in Wales received 4,408 calls in the 12 months to March this year from children. In the same period up to March 2003, the helpline responded to 2,803 calls.
The charity also warned that bullies were increasingly using threatening text and e-mail messages.
Jonathan Green, the head of ChildLine Cymru said he hoped the increase in calls was at least partly due to young people being encouraged to report and seek help about being bullied.
He said: "It could be because they're getting the message that bullying doesn't have to be tolerated - I would hope it's because children feel they can speak out if they're being bullied.
"It can leave them feeling worthless, traumatised and afraid to go to school, and that can have an effect lasting right into adulthood."
Mr Green said it was also "quite frightening" that one in four of those who had called had already reported being bullied to a teacher.
World boxing champion Joe Calzaghe, from Newbridge - who suffered from bullying as a teenager - urged children who were being targeted by bullies to speak up about the problem.
The 2004 figures are revealed by the charity as it launches a new fundraising initiative - the ChildLine Foundation.
ChildLine's chair Esther Rantzen said: "Our volunteer counsellors tell us that the calls they receive about bullying are some of the most painful they encounter at ChildLine.
"While many schools have taken positive steps in recent years to acknowledge that bullying exists and to tackle the problem, as ChildLine's new figures show, there is still much to be done."
ChildLine Cymru/Wales has helped more than 20,000 victims of bullying through its helpline centres in Rhyl and Swansea.
It offers both Welsh and English language services.
So far, the charity has helped 150,000 children in Wales since it was set up in 1993, saving lives, protecting youngsters from abuse and found shelter for children on the streets.
The free UK-wide helpline service was set up in the 1980s, following an appeal on the BBC programme That's Life for viewers' help in conducting a survey on child abuse.
The helpline now receives more than 138,000 calls each year.