Behaviours of concern can look very different from one person to the next. For one person it might be hitting out when a routine changes. For another it might be head banging, running from home or quietly shutting down for hours.
Each type of behaviour has its own patterns, causes and risks. Understanding these differences helps families, carers, support workers and practitioners describe what’s happening clearly, and it’s the starting point for the right support.
What Are Behaviours of Concern?
Behaviours of concern are behaviours of such intensity, frequency or duration that a person’s safety or wellbeing is at significant risk. It’s the term used by the NDIS and across the Australian disability sector.
A behaviour isn’t a concern just because it’s unusual. It becomes one when it causes harm, or when it stops a person from taking part in school, work, relationships and community life.
1. Physical Aggression
Physical aggression is any behaviour directed at another person that can cause harm. It’s one of the most common reasons people are referred for behaviour support.
What it can look like:
- Hitting, slapping or punching
- Kicking or stomping
- Biting, scratching or pinching
- Hair pulling
- Pushing, shoving or headbutting
- Spitting or throwing objects at people
Why it happens: Aggression often works for the person, even if it causes harm. It might get them out of a task, get them an item they want, or bring people running. For many people, it’s the fastest way to say “stop” or “no” when they can’t yet communicate that another way.
Why it’s a concern: Aggression can injure family members, support workers, teachers and peers. Over time, it can lead to the person being excluded from school, losing support workers or having fewer opportunities to go out.
2. Self-Injurious Behaviour
Self-injurious behaviour is when a person causes harm to their own body. It’s often one of the most distressing behaviours for families to witness.
What it can look like:
- Head banging against walls, floors or furniture
- Biting hands, wrists or arms
- Hitting or slapping their own head or face
- Scratching, picking or gouging skin
- Pulling out hair
- Eye poking
Why it happens: Self-injury can help a person escape a demand, get help quickly or block out sensory overload. For some, the sensation itself is reinforcing. Pain and other physical factors can also play a part, especially when a person can’t easily say they’re hurting.
Why it’s a concern: Self-injury can cause bruising, wounds, infections and lasting damage, including to the eyes and head. Because of the risk of serious injury, it’s often treated as a priority in behaviour support.
3. Property Destruction
Property destruction is behaviour that damages objects, belongings or surroundings.
What it can look like:
- Throwing or smashing items
- Tearing clothes, books or paperwork
- Kicking or punching holes in walls and doors
- Breaking furniture, devices or windows
- Damaging cars or other vehicles
Why it happens: Property destruction is often linked to frustration, wanting to escape a task or getting a strong reaction from others. For some people, the sound, sight or feel of something breaking is part of the appeal.
Why it’s a concern: It can be costly for families and services, and broken glass or damaged furniture can create new safety risks. It can also lead to the person losing access to belongings, activities or living arrangements.
4. Verbal Aggression
Verbal aggression is the use of words or sounds in a way that frightens, threatens or hurts others.
What it can look like:
- Screaming or yelling
- Swearing at people
- Threatening to hurt others
- Name-calling or insults
- Loud, repeated vocalisations directed at others
Why it happens: Verbal aggression often happens when a person feels overwhelmed, frustrated or misunderstood. It can also be a way of keeping people at a distance or getting out of a situation.
Why it’s a concern: Although it doesn’t cause physical injury, verbal aggression can frighten others and damage relationships. It’s also often an early warning sign that physical aggression may follow.
5. Absconding
Absconding, also called elopement or bolting, is when a person leaves a safe place or supervision without permission.
What it can look like:
- Running away from a parent or carer in public
- Leaving home, often at night
- Walking out of school, a day program or a group home
- Bolting towards roads, water or open spaces
Why it happens: People may run to escape something unpleasant, like noise or a difficult task. Others run towards something they find interesting, or enjoy the excitement of being chased.
Why it’s a concern: Absconding carries some of the highest risks of any behaviour of concern, including traffic accidents, drowning and getting lost. Even when it happens rarely, it’s taken very seriously.
6. Sexualised and Socially Inappropriate Behaviour
This type covers behaviours that are risky mainly because of where, when or with whom they happen.
What it can look like:
- Undressing in public or invading other people’s personal space
- Touching others without consent
- Sexualised behaviour in public places
- Smearing bodily waste
- Inappropriate comments or gestures
Why it happens: These behaviours usually point to a skill that hasn’t been learned yet, such as understanding privacy, body boundaries or the difference between public and private places. Sensory needs can also play a part.
Why it’s a concern: Without support, these behaviours can expose a person to stigma, exploitation, harm or legal trouble. They can also lead to exclusion from community settings.
7. Pica
Pica is repeatedly eating things that aren’t food and have no nutritional value.
What it can look like:
- Eating soil, sand or stones
- Eating paper, cardboard or fabric
- Eating soap, paint or cleaning products
- Swallowing small objects like buttons or batteries
Why it happens: Pica can be linked to sensory needs, such as enjoying certain textures. In some cases, it may be connected to nutritional deficiencies, which is why medical input matters.
Why it’s a concern: Pica can cause bowel blockages, choking, tooth damage and poisoning. Because the risks can be life-threatening, it usually involves a GP alongside behaviour support.
8. Non-Compliance and Refusal
Non-compliance is when a person consistently refuses to follow requests or take part in activities.
What it can look like:
- Refusing instructions
- Dropping to the floor
- Walking away from tasks
- Pushing activities or materials away
- Refusing to leave a place or activity
Why it happens: Refusal often looks like defiance, but it’s usually a sign that a task feels too hard, too long or too unclear. Changes in routine and transitions are common triggers.
Why it’s a concern: When refusal is ongoing, it can stop a person from attending school, completing personal care or taking part in community life, and it can affect their health and independence.
9. Repetitive Behaviour
Repetitive behaviour includes movements, sounds or routines that a person repeats often.
What it can look like:
- Rocking or spinning
- Hand flapping
- Repeating words, phrases or sounds
- Rigid routines or rituals
- Distress when routines change
Why it happens: Much of this is stimming, which helps many autistic people manage strong emotions and sensory input.
Why it’s a concern: Repetitive behaviour isn’t a concern in itself. It’s only treated as a behaviour of concern when it causes injury or gets in the way of learning or daily life.
10. Withdrawal
Withdrawal is when a person pulls away from people, activities or their surroundings.
What it can look like:
- Shutdowns, where the person stops responding
- Refusing all contact with others
- Hiding or staying in their room for long periods
- Losing interest in activities they used to enjoy
Why it happens: Withdrawal can be a response to feeling overwhelmed, anxious, unwell or unhappy. It’s sometimes a way of coping with too much noise, demand or change.
Why it’s a concern: Because withdrawal is quiet and doesn’t disrupt others, it’s easily overlooked. Over time, it can lead to isolation, missed opportunities and declining mental health.
Final Thoughts
Behaviours of concern take many forms, from aggression and self-injury to running away, pica and withdrawal. Each type looks different, but they have one thing in common: the behaviour is doing something for the person. A behaviour support practitioner looks at what the person is trying to get, or get away from.
Knowing the type of behaviour helps describe it clearly. Understanding why it’s happening is what leads to real change. That’s the focus of Positive Behaviour Support, where the reasons behind a behaviour shape a behaviour support plan designed to improve the person’s quality of life, not just reduce incidents.
If behaviours of concern are affecting someone’s safety or wellbeing, a qualified behaviour support practitioner can help uncover what’s driving them and put the right support in place.