Failing to report allegations of child sexual abuse should be made a criminal offence in Britain, the former director of public prosecutions said.
Keir Starmer believes it is time to "change the law" and said it should be "mandatory" to report allegations.
Speaking on BBC Panorama, Mr Starmer said: "I think the time has come to change the law and close a gap that's been there for a very long time.
"I think there should be a mandatory reporting provision.
"The problem is if you haven't got a central provision requiring people to report, then all you can do is fall back on other provisions that aren't really designed for that purpose and that usually means they run into difficulties.
"What you really need is a clear, direct law that everybody understands."
Mr Starmer told the programme he has spent a lot of time thinking about how the criminal justice system could improve its response to child sexual abuse.
"I went to Washington to see how the specialist teams there deal with it," he said.
"They do have a mandatory reporting scheme, a very straightforward, simple scheme and something like that I think could work in this country."
Abuse lawyer Liz Dux, of Slater & Gordon, who represent more than 70 of Jimmy Savile's victims, said: "The Savile scandal has prompted a welcome shift in attitude towards child abuse - but there is so much more that needs to be done to make sure evil like this can never prosper again.
"It is vital lessons are learnt and our clients are determined that something positive comes out of the terrible abuse they suffered."
She added: "Since the Savile scandal some steps have been taken to assist victims through the difficult process of reporting abuse and the criminal trial process - but now the Government needs to act in a more positive way to make sure the silence that surrounded Savile and allowed his horrific abuse to go unreported can never happen again.
"We are now calling on the Government to introduce legislation whereby those in regulated activities who have direct knowledge of abuse and fail to do the right thing and report it will face prosecution.
"This will better protect people in the future. We owe this reform to the victims of abuse who have been failed in the past but remain courageous enough to speak out now."
The Mandate Now coalition also called for the reporting of child abuse to become mandatory.
Napac (the National Association for People Abused in Childhood), The Survivors Trust, Respond, Survivors UK and Innocence in Danger are calling for mandatory reporting to be introduced in schools and similar institutions, where children are cared for in loco parentis.
Jonathan West, a Mandate Now campaigner, said: "Time after time we hear that head teachers and other professionals have failed to act on reports and concerns, and little is ever done to address this very serious shortcoming.
"Staff also need legal protection from the recrimination which can so easily follow when a person takes the courageous step of reporting a concern."
However, the Government currently has no plans to change the law - with the Department for Education stating that mandatory reporting is "not the answer".
A spokesman said: "Guidance is already crystal clear that professionals should refer immediately to social care when they are concerned about a child.
"Other countries have tried mandatory reporting and there is no evidence to show that it is a better system for protecting children.
"In fact there is evidence to show it can make children less safe."
Panorama: After Savile: No more secrets? is on BBC One tonight at 8.30pm.
Mr West told BBC Radio 4's Today programme that institutions were reluctant to go to the police over allegations of child abuse because they did not want to be involved in a scandal.
He said: "Schools and other organisations often don't really want to have a child abuse scandal on their hands."
It was "surprisingly common" for schools to attempt to deal with the matters in-house, he claimed.
Dame Clare Tickell, chief executive of Action for Children, told the programme there was "absolutely no justification whatsoever" for not reporting abuse if identified.
But she added: "What we want is for people across the system... not just social workers, we want people working in the health system, people working in the education system, to know exactly what it is they need to identify and think about and how they spot those early signs and not to feel that they may be prosecuted if they don't do it."
Shadow crime and security minister Diana Johnson said: "We support professionals being under a clear duty to report child abuse to make sure we stop this heinous crime at the earliest opportunity.
"We must take the call of the retiring DPP for nurses and teachers to be under a legal duty to report allegations of child abuse very seriously. We must also examine whether all public service employees and others should be under a similar obligation.
"We know a number of allegations were made about Jimmy Savile to professionals and no action was taken. More recently in the Daniel Pelka serious review case, many professionals missed the opportunity to rescue the little boy from torture and starvation. It is now right to consider strengthening the law to protect our children.
"Looking at the practical experience of countries who already operate such a system is important as well as working with all the professional bodies to create a better system of information sharing and training."