The length of time that an item receives copyright protection is determined by what type of material it is.

The period of protection is always calculated from the end of the relevant calendar year. When reference is made to the life of the author, the period is calculated on the author's life – even though the copyright may be owned by someone else. Copyright will in many cases last longer than the life of the author or owner of copyright. Because copyright itself is property this means it that can be bequeathed (given away) under the copyright owner's will.

A further factor affecting some materials will be whether it was published anonymously or under a pseudonym. In these cases the date from which copyright duration is calculated is the date of first publication rather than the death of the author given this is unknown.

Once copyright has expired the material enters the public domain and may be used without obtaining permission. For a guide to identifying whether copyright has expired and what types of material are available in the public domain see the Australian Copyright Council’s Duration of Copyright factsheet.

After the date of expiration copyright cannot be extended or renewed.

Where a work is unpublished copyright continues to exist for as long as the work remains unpublished.

Some types of material have expanded copyright periods as a consequence of the Australia-US Free Trade Agreement which came into effect on 1 January 2005. For example, published photographs previously had a copyright duration of 50 years but, under the agreement, this has period has been extended to 70 years.