There is no internationally agreed definition of homelessness. 

 

According to the Australian Bureau of Statistics (ABS) a person who does not have suitable accommodation alternatives is considered homeless if their current living arrangement is:

​

• in a dwelling that is inadequate; or 
   
• has no tenure or if their initial tenure is short and not extendable; or​​
   

• does not allow them to have control of or access to space for social relations. 
   

This definition is informed by an understanding of homelessness as ‘home’lessness as opposed to ‘roof’lessness. 

​

Mackenzie and Chamberlain when gathering information for a Census of Population, decided upon a cultural definition to measure homelessness and define community standards on the minimum housing that people have the right to expect. 

​

They created three distinct categories:

​

• Primary homelessness, referring to people sleeping rough or living in improvised dwellings as opposed to conventional accommodation.
   
• Secondary homelessness, referring to  people who frequent emergency accommodation, refuges or who are forced to couch surf. 
   
• Tertiary homelessness, referring to people forced to live in accommodation that is considered to be below community standards. 

​

The United Nations divide homeless people into two groups:

​

• Primary homelessness (or rooflessness), referring to people living in the streets without a shelter.

​

• Secondary homelessness, people without a usual residence who are forced to move frequently between various types of insecure accommodation.​