Australian rules and regulations
Domain names with the Australian .au suffix, are subject to many rules regarding the eligibility of registrants and the allocation of the domain names. For full details see Domain Name Eligibility and Allocation Rules at AUDA. Here is a brief summary for each:

.COM.AU & .NET.AU
Registration limited to Australian registered company, or business, who meet one of the following criteria:

• An exact match of the business' name or trademark
• An abbreviation of the business' name or trademark
• An acronym of the business' name or trademark
• Product that the business manufactures or sells
• A program that the business administers
• An activity that your business facilitates, teaches or trains
• A service that your business provides
• A venue that the business operates
• A profession that is practiced by the business' employees or members
• An event that your business organises or sponsors
• Place names in Australia are disallowed as domain names
• Domain names can be 2 to 63 letters, and words can be separated by hyphens

.ORG.AU
Registrant must be a registered company, or business, or incorporated association whose articles of association specify the entity as a charity or not-for-profit organisation. The business must also meet one of the following criteria:

• exactly match the name of the registrant's association, political party, trade union or other industry body, or club; or
• be an acronym or abbreviation of the name of the registrant?s association, political party, trade union or other industry body, or club; or
• be otherwise closely and substantially connected to the registrant, because the domain name refers to:
  1. a service that the registrant provides; or
  2. a program that the registrant administers; or
  3. an event that the registrant organises or sponsors; or
  4. an activity that the registrant facilitates, teaches or trains; or
  5. a venue that the registrant operates; or
  6. a profession that the registrant's members practise.

.ASN.AU
Registrant must be an incorporated association, registered political party, registered trade union, or a sporting or special interest club operating within Australia, and meet one of the following criteria:

• exactly match the name of the registrant's association, political party, trade union or other industry body, or club; or
• be an acronym or abbreviation of the name of the registrant's association, political party, trade union or other industry body, or club; or
• be otherwise closely and substantially connected to the registrant, because the domain name refers to:
  1. a service that the registrant provides; or
  2. a program that the registrant administers; or
  3. an event that the registrant organises or sponsors; or
  4. an activity that the registrant facilitates, teaches or trains; or
  5. a venue that the registrant operates; or
  6. a profession that the registrant's members practise.

.ID.AU
Registration limited to individuals who reside in Australia who are a citizen or resident of Australia, and the domain name is:

• an exactly match the registrant?s personal name ; or
• an acronym or abbreviation of the registrant?s personal name; or
• closely and substantially connected to the registrant, because the domain name: derived from the registrant's personal name; or includes the registrant's personal name.