Summary
Read the full fact sheet- Appointing a medical treatment decision maker gives someone the power to make medical choices for you if you are unable to.
- To appoint a medical treatment decision maker, fill in the appointment form, sign it and have two people witness it (make sure you check all the witnessing requirements).
- As long as you are legally competent, you can change your medical treatment decision maker at any time.
- You can also appoint more than one person to be your medical treatment decision maker if you wish.
- Tell your medical treatment decision maker what you think about life support, surgery, medication and anything else that could be relevant.
- Make sure your doctor knows who your medical treatment decision maker is.
On this page
- What is a medical treatment decision maker?
- Reasons to have a medical treatment decision maker
- Communicate your views with your medical treatment decision maker
- How to appoint a medical treatment decision maker
- Appointing a medical treatment decision maker when a person does not have capacity
- How to change your medical treatment decision maker
- Your role as medical treatment decision maker
- Where to get help
What is a medical treatment decision maker?
You can nominate someone you trust to make decisions about your healthcare on your behalf, in the event that you suffer an injury or medical condition that affects your ability to make those decisions yourself. The person you nominate is known as a medical treatment decision maker.
Your medical treatment decision maker is legally bound to act in a way that promotes your personal and social wellbeing. This means that they must consider your medical preferences, values and beliefs in order to make the decision they believe you would have made, were you able to.
You do not have to lose capacity permanently. For example, if you are injured or ill temporarily, your medical treatment decision maker can make treatment decisions for you until you recover.
A medical treatment decision maker cannot make financial or property decisions for you. That requires a different type of legal appointment – learn more at the Office of the Public Advocate website.
Reasons to have a medical treatment decision maker
If you have a medical condition or life-limiting illness that affects your ability to retain new information and make decisions, appointing someone to be your medical treatment decision maker is a good course of action.
Some examples of conditions that may put you in this position include:
- acquired brain injury
- cognitive (thinking) impairment
- unconsciousness
- inability to communicate (for example, after suffering a severe stroke)
- dementia.
Other situations where you may choose to appoint a medical treatment decision maker include:
- if you do not want life support at a certain point in an illness or after an accident
- if you are worried you may be injured performing a certain activity, such as playing a high-contact sport.
Communicate your views with your medical treatment decision maker
It is important to talk to your medical treatment decision maker about your views on and wishes for any medical treatment you may need and make sure they are clear about your choices. This could include surgery, types of medication and life support systems.
It is a good idea to write down your thoughts, using an advance care directive for example, so that your medical treatment decision maker and the rest of your family and friends are clear about your wishes.
Find out more about recording your wishes for future care on the Advance care plans page.
Advance care planning forms can be found on the Department of Health website.
How to appoint a medical treatment decision maker
You can appoint a medical treatment decision maker at any time so long as you are over 18 years and of sound mind. Remember, their role only begins if and when you lose the ability to make your own medical decisions.
To appoint a medical treatment decision maker, you must:
- fill in the Appointment of medical treatment decision maker form
- sign the form
- have it witnessed by two people – one of the two witnesses needs to be a qualified person, such as a Justice of the Peace.
To accept the appointment, your medical treatment decision maker will also have to sign the form in front of your witnesses.
Make sure you keep the original form somewhere safe and tell a few trusted people where it is. You should also give copies to your medical treatment decision maker, your doctor and your local hospital.
Keep your medical treatment decision maker's contact details with you at all times in case of emergency, and tell your close family members and friends who your medical treatment decision maker is.
Appointing multiple medical treatment decision makers
You can appoint more than one person to be your medical treatment decision maker. However, only one person will be able to act on your behalf at any given time.
If you were to lose capacity and a decision had to be made on your behalf, the first person you appointed will act as your medical treatment decision maker. If they are unavailable, then the second appointee will become your medical treatment decision maker, and so on.
Appointing a medical treatment decision maker when a person does not have capacity
Where a person does not have decision making capacity to appoint a medical treatment decision maker, the Medical Treatment Planning and Decisions Act 2016 identifies who will be given this role.
Medical treatment decision makers must be reasonably available to be contacted as needed, and be willing and able to undertake the role.
Further information on appointing a medical treatment decision maker can be found at the Office of the Public Advocate’s website.
How to change your medical treatment decision maker
If for some reason you wish to revoke the appointment of your medical treatment decision maker, you must complete a Revocation of medical treatment decision maker form and have it witnessed by two people. One of these witnesses must be qualified to witness affidavits.
You must also take reasonable steps to let your previous medical treatment decision maker know that you have revoked their appointment. However, if for some reason you are unable to let them know, the revocation will still be valid.
Your role as medical treatment decision maker
If someone wishes to appoint you as their medical treatment decision maker, you are being put in a position of trust. Your first act should be to discuss with the person appointing you what their opinions are on particular medical issues, especially things like the use of life support machines and surgical procedures. You may want to write down their wishes to avoid confusion later on, especially if some time has passed since you were appointed.
Once your role as medical treatment decision maker begins (when the person is unable to make their own decisions), it is your responsibility to do your best to make the same decisions the person would make if they were able to. You need to make sure you are always available to consult with any doctors and others in the person’s medical team.
Where to get help
- Your GP (doctor)
- Your lawyer
- Victoria Legal Aid
- Office of the Public Advocate
- Victorian Palliative Care Advice Service
This page has been produced in consultation with and approved by:


