The Garda Inspectorate has criticised An Garda Síochána for continuing to involve inexperienced and untrained officers in all aspects of child sexual abuse investigations.
The Inspectorate has published its review of the gardaí's response to the crime, and said it was "disappointed" that less than half of the recommendations from its previous report five years ago had been implemented.
It also found there are still long delays in the forensic examination of suspects' computers and says gardaí need to be more pro-active online to target child sex abusers.
According to the Inspectorate, there has been a considerable increase in the risk to child safety posed by the internet and social media in the last six years.
In 2012, it examined how gardaí investigated the crime of child sexual abuse and made recommendations on how they could do better.
However when the Inspectorate checked again last year on what progress had been made, it was in its own words "disappointed".
It found that out of the 29 recommendations, 13 had been implemented; six partially implemented; and six more not implemented at all.
The Inspectorate said the remaining four recommendations had not been satisfactorily addressed.
It found that inexperienced and untrained gardaí are still involved in all aspects of a criminal investigation, an approach it says is not used in other police services and is not good practice.
It also said in spite of increased resources there are still long delays in the forensic examination of computers of suspected sex offenders which continue to present significant organisational risks, and it recommends a new approach to reduce the backlog.
While the Inspectorate has welcomed the recent announcement of an increase in the number of online garda investigators, it says that gardaí need to have a more pro-active online presence to target those grooming children and those accessing sites that contain child abuse material.
The Inspectorate said that more specialist child interviewers must be trained and joint interviewing by gardaí and social workers needs to be reintroduced because it is in the best interests of the child to have just one interview.
The report also highlights the dangers to children from technology, sexting and the fact that many children do not report exploitation and abuse.
It recommends that gardaí with the other agencies conduct an annual assessment of the scale and severity of child sexual exploitation and develop investigative and preventative techniques to protect children.