The government has made little progress in bringing child sex abusers to justice and helping victims, a new report has claimed.
Fewer child sex offenders are being convicted, according to the report
Children in care are safer, but fewer than one in 50 sexual offences leads to a criminal conviction, the Joseph Rowntree Foundation charity said.
Its study was overseen by Sir William Utting, who led an official review of abuse of children in care in 1997.
The government is set to consider the findings, to be published on Monday.
Sir William told BBC Radio 4's Today Programme there had "not been much progress" in securing sexual abuse convictions and treating sex offenders over the last seven years.
The former chief social services inspector added: "We need to convict more guilty people and encourage offenders to come forward voluntarily for treatment, as well as providing them with treatment."
The Bichard Inquiry's call for better handling of "soft" information - such as anecdotal evidence of past wrongdoings - must be heeded to prevent abusers falling through police checks, according to the report.
It calls for a public awareness campaign to give parents greater help spotting the dangers.
Co-author Marian Stuart warned: "The incidence of sexual abuse of children is greater than most people realise, yet the number of convictions remains worryingly low.
"If this problem continues to go unchecked there will be an inexorable rise in the numbers of children subjected to sexual abuse, with all the damaging effects that can follow.
"A radical rethink is essential."
Susanna Cheal, chief executive of the Who Cares? Trust - a charity dedicated to helping children in care - said the low conviction rate for paedophiles was largely due to the "power balance" between abusers and victims.
She said: "Abuse is often likely in a situation where adults have supreme power over children.
"Sometimes it is hard to prove the situation in legal terms - a lot of children feel vulnerable when pitted against adults in court."
Ms Cheal said it is important for children to "have a voice" by contacting support networks in ways they are comfortable with, such as by text or email.
Sir William said it had been difficult to raise the number of convictions because offenders must be found guilty beyond reasonable doubt, which is "extremely difficult" to prove where children are concerned.
He called for "more sensitive and thorough investigation of these cases, rather than a change in the level of proof" to combat this problem.
However, improvements have been made concerning children in care and other "vulnerable" children, such as those at boarding school.
"The number of children abused in children's homes has gone down," said Sir William.
"Good progress has been made - the services they receive have improved markedly and they are safer than they were."
There are particular concerns over children with disabilities, psychiatric problems and those who are privately fostered.
Prisons are also failing the increasing numbers of youngsters who find themselves behind bars.
The report also calls for more research into why people offend.