Determination at national and international level is required to root out serious criminals who are using the Internet to make "enormous money abusing children", the Tánaiste told the Dáil.
Ms Harney said that Ireland had strong legislation in this area and there had been a number of Garda investigations and prosecutions, but if there were any gaps in the legislation or if it was an issue of resources, this would be resolved.
"At the end of the day it is important that we have the determination and vigour at national and international level through co-operation with police authorities to be able to root out those who are making enormous money abusing children.
"That is what is happening here. The abuse of children by serious criminals is something that all of us have to co-operate in fighting and combating." The Tánaiste was answering questions following the broadcast of a Prime Time investigation into Internet child sexual abuse.
Mr Caoimhghín Ó Caoláin (SF, Cavan-Monaghan) said that in child abuse the "issue is opportunity and the Internet has provided opportunity on a scale never seen before". The documentary revealed that those accessing sites linked to child pornography were obliged to provide their own images before they could view images from other users.
Referring to statistics from Women's Aid, he said there was a "great need to recognise that often those who abuse their wives or partners are also likely to be abusers of children. Abuse of women and children in the home is an unseen crime being perpetrated throughout this island and globally".
Mr Ó Caoláin expressed concern that a media investigation and not a Garda one, exposed the extent of the abuse, and he asked if gardaí dealing with this abuse "are properly resourced and have the necessary strategies to address this sick pursuit".
"One of the downsides of the development of modern technology is that it increases the scope for widespread abuse of this kind," Ms Harney replied.
She had not seen the programme, but described it as an act of public service broadcasting, which had had a major impact and if any response from Government was required either through legislation or resources, it would be provided. She also stressed the concern at European level and the international co-operation, which had led to a number of successful prosecutions recently.