Its terms of reference have yet to be officially decided, but the royal commission into sexual abuse in institutions run by governments, churches and community has already been given a potentially wide brief by the Prime Minister. In announcing the inquiry on Monday, Julia Gillard declared there would be no deadline for completion, and that ''victims must be allowed to heal, and perpetrators must be brought to justice''.

These are lofty ambitions, certainly, but many of the victims and their families are likely to be profoundly appreciative. Like a good many other countries, the abuse of children and young adults within institutions has been longstanding and widespread in Australia.

The shame, betrayal and confusion felt by the victims meant that not all of these incidents were reported. Those that were - either to senior church authorities or the police - were frequently denied by the perpetrators and their accomplices after the fact.

To protect the reputation of their churches, senior clergy members have conspired in cover-ups or actively frustrated police investigations.

The psychological damage suffered by the victims was exacerbated by the cruelty and indifference shown them by the institutions allegedly charged with their care and guidance. It led to blighted lives, and in many cases suicide.

This inquiry is official recognition of the extent of the crimes against them, and while perhaps over, to be welcomed nonetheless.

Equally welcome is the promise of broad terms of reference.

Were a royal commission to adopt a sectarian approach and ignore state care institutions, schools, sporting clubs and not-for profit groups, it would run a serious risk of failing to deal adequately with the size and enormity of the problem.

That many church leaders have already pledged their full support and co-operation is encouraging.

However, a royal commission might not be the panacea that some people, including the Prime Minister, imagine it will be.

Evidence gathered in inquisitorial settings is generally inadmissible in a court of law, raising doubts that all of the perpetrators will be brought to justice, as Ms Gillard has vowed. A handful of state-based inquiries into child abuse are now under way, and the establishment of a national royal commission has the potential to muddy the waters of continuing investigations - and to create the climate for unhelpful political distractions.

The prospect of an inquiry lasting five years or even longer also raises potential problems, not the least of them being funding. Ireland's Commission to Inquire Into Child Abuse (popularly known as the Ryan Commission) took nine years to complete, and its findings ran to five volumes totalling 2500 pages.

The government of the time also established a compensation scheme that paid out almost one billion euros in compensation, as well as meeting the legal fees of 12,500 people. For the sake of the victims, and the organisations who will be called to account, this royal commission cannot be allowed to be as drawn out as that.

If the inquiry is to be a vehicle for healing (as Ms Gillard has also appeared to suggest), great care must be taken to provide a forum for those victims who have so far remained silent, whether out of a sense of disempowerment brought about by deep feelings of shame, or by lack of confidence in authorities to respond to the painful experiences in an appropriate and timely fashion.

The inquiry needs to be conducted in a way that recognises their deep and lasting wounds. They deserve the utmost sympathy and respect.

It might be argued that an inquiry of this kind cannot deliver both justice and closure to all the parties, in which case Ms Gillard (or more realistically her successor) might care to contemplate a truth and reconciliation commission run along the lines of the one that healed many of the wounds incurred in South Africa's apartheid past.

If the Irish example is an accurate guide, an official apology and compensation may be an unavoidable outcome of a royal commission.

If the recommendations of the inquiry are acted on promptly, there is every chance this process will be a healing one.

Most importantly, measures must be put in place to stop, once and for all, the institutionalised abuse that has blackened the name of so many organisations for so long and left so many lives in ruin.