I have always believed that one person's problems cannot be allowed to become another person's nightmare. This belief applies to both adults and children. It is now the legal situation that children who are at risk from parents or teachers or other adults are protected under the law. Physical, sexual and emotional neglect of children is now unlawful.

However, laws in themselves are rarely effective enough to bring about physical, psychological and social harmony. There are deep reasons why adults lash out at children and unless these are dealt with in an understanding and compassionate way, it is unlikely that individual maturity and social harmony will evolve.

Nonetheless, the law does offer some level of protection for children who are at risk.

But what about adults who are at risk from children who are dangerous and verbally abusive? I know of many parents who suffer greatly at the hands of their children and for years teachers have been complaining about a rising tide of discipline problems.

Indeed, many teachers who were good at teaching have left their jobs due to impossible discipline situations. A recent benchmark decision by the High Court in London may pave the way for change in Ireland. The court ruled that "teachers could not be forced to teach a disruptive pupil". The teaching unions have welcomed the decision, insisting that their members must be protected from children who exhibit dangerous and/or abusive behaviour.

A similar ruling is needed for parents who are at risk from their children. Hopefully, any such ruling in Ireland would help to stem the exodus from teaching and lead to the creation of appropriate interventions for children who manifest aggression, particularly those children who have been excluded from school.

In England, the number of exclusions has risen from 2,910 in 1991 to 10,400 in 1999. My guess is that the four-fold increase is mirrored here in Ireland.

Teachers and parents are not counsellors, psychologists, family therapists or social workers. For too long, teachers have been expected to cope with students who are disruptive. Regrettably, much of some teachers' own aggressiveness and use of cynicism and sarcasm arose from attempts to counter-control pupils who manifested disruptive behaviours.

Hopefully, the clear legal ruling means that neither teacher nor pupil will have to put up with such behaviours any longer and will lead to an improved classroom and school ethos.

While laws are desirable to provide safety to those who are at risk from the threatening behaviour of others, the laws do not resolve the reasons why children or adults act in ways that lessen the presence of others.

There are many reasons why children show aggression; the causes are often similar to children who are depressed, fearful, timid, perfectionistic, withdrawn and obsessive-compulsive. However, because these latter behaviours are not a source of threat to adults and other children, these children are tolerated in classrooms and homes.

Nevertheless, these children require as much help as those who show aggression. Possible source of children's disruptive actions are: low self-esteem; insecure home situation; too much responsibility; over-protective parenting; pressure to perform academically; poor relationship with parent; open conflict at home; modelling of violence and verbal aggression by a parent; bullying by other children and/ or by a parent/teacher; sexual abuse.

The above list is not exhaustive; indeed, it is unwise to assume that there are common causes for aggressive behaviour. Real understanding attempts to source the reasons that are unique to a particular child.

Timing, patience and a willingness for adults to look to their own ways of relating to children and each other help.

The issue of timing is important as, with a child, there is no point in attempting to probe the reasons for the difficult behaviour when he or she is shouting, screaming or hitting.

It is essential for the adult to remain calm, not to personalise the outburst and not to attempt to control the young person.

Only when the child has calmed down should the "I really want to know what has upset you and what is it that you need" be voiced.

Certainly, such an attempt to understand must not weaken the resolve to ensure safety for those who are under threat. However, progress is much more likely to be made when parents, teachers and other adults work on both tracks - safety for selves and others and understanding and action for the child who has perpetrated the disruptive action.

Issues of the frequency, intensity and endurance of the threatening behaviours are also important in determining the urgency and the nature of intervention that is needed to resolve young people's physical and verbal aggression and other disruptive behaviours.

Dr Tony Humphreys is a consultant clinical psychologist and author of A Different Kind of Discipline