I well remember the amazement and horror with which, as a field social worker, I came across my first case of sexual abuse 20 years ago. Not only was there little help available from colleagues, but there was also a dearth of useful literature.
The position is now very different: sexual abuse of children is recognized to be quite common and it probably always has been. Moreover, in the developed world, the commonest form is abuse by someone known to a child.
Handbooks, research and procedural guides proliferate. These are complemented by personal accounts from those directly involved.
By and large they do not like the term "victim", and much prefer to call themselves "survivors". Survivor accounts make painful reading, but it is not difficult to empathise with them.
The Memory Bird is such a collection. It includes prose narratives and poems from a wide range of people, both men and women, who are all survivors of sexual abuse. Some of the texts are raw with emotion, some calm, articulate and poised. Literary merit is not, however, the issue with this kind of writing, but the authenticity that springs from personal experience.
But there is one point of view which most people are content to leave in darkness - that of the perpetrator.
Who wants to understand their view of their crime? This is what Colton and Vanstone have done.
In the first account of its kind I have come across, there are the views and experiences of perpetrators themselves.
This is a most professional piece of work. The authors each combine practical experience with academic work, and they have given proper consideration to all questions of confidentiality, consent and the nature of the material they discuss. There is no prurience.
They freely admit that their group of seven men is too small to be representative and is not typical of the pattern of sexual abuse. For example, they have no case of a man who has abused his daughter or stepdaughter.
What these seven men have in common is that they held positions of trust with children, some of them in senior posts. Two were teachers and one was a priest. While in prison, they were the subjects of a treatment programme run by the authors .
The bulk of the book consists of transcripts of their side of interviews - exploring their early life, their sexual development, their education and employment, how they perpetrated the abuse and the impact of the treatment programme.
As you follow these through you see how natural and inevitable the slide into abuse became and the devices they used to regard it as something else.
There are some themes in common including a poor relationship with their fathers and a tendency to find children easier to relate to than adults. They have all abused power and a position of trust. Macho cultures have had a corrupting effect on them.
But what is both more striking and more disturbing is their basic ordinariness. The authors show great skill in bringing this out without in any way minimising or trivialising their offences and the result is far more compelling than the kind of account which demonises.
The other remarkable thing about these accounts is their honesty. As the authors point out, not all abusers are amoral, and guilt, remorse and a desire not to abuse are all part of the picture.
It becomes easier to understand their motivation if we see abusive behaviour as being like - indeed, being a form of - addiction, with the perpetrators going round a cycle of desire and indulgence that constantly repeats. They all have difficulty accepting - if they ever do accept - that a child cannot give a valid consent to sexual activity, which is what makes their behaviour abusive.
This means that the aims of treatment programmes have to be limited. Probably the best we can hope for is, as with alcoholics, that they stop abusing.
We cannot expect a fundamental personality change, particularly from mature adults with deeply entrenched behaviour patterns. But we cannot just ignore the issue. Even prison sentences come to an end.
Finally, the authors make some suggestions for improvement. Changes in prison regimes would help, as currently these do little to reduce the risk of reoffending.
Better awareness of warning signs by others and action on them is also needed. Police checks should be more widely available.
More controversial is the proposal for helplines for perpetrators, not as an alternative to prosecution but to support and encourage those who want to refrain from offending. These may not work, but no one seems yet to have tried them.