For a Proprietary Company - one (1).
If an overseas Director is appointed to a Proprietary Company it must also have an Australian Resident as a Director.
For Unlisted Public Companies and Limited by Guarantee (LBG) there is a minimum of 3 directors and at least 2 must be Australian residents.
Directors must be at least 18 years old and must not be a disqualified person per the Corporations Act 2001.
