In Australia, copyright in published works generally lasts for the life of the author/creator plus 70 years (or if the author/creator is unknown, 70 years after the work is first made public).
The duration of copyright in subject matter other than works (films and sound recordings for example) is more variable, but generally is 70 years from the end of the year of first publication.
There are variations from these general rules. Before 1 January 2005, the term of copyright in Australia was life of the author plus 50 years for published works, and 50 years after publication for audio-visual items. The extended term of 70 years applies only to material that was still in copyright on 1 January 2005. If the copyright had expired by that date, it stays expired.
Crown Copyright refers to material made or first published by state, territory or commonwealth government. The term of copyright for these works is generally 50 years after date made.
For more information, read this comprehensive table prepared by the Australian Government’s Department of Communication and the Arts: Duration of Copyright
Recent amendments to Duration
Under the Copyright Amendment (Disability Access and Other Measures) Act 2017, new terms of protection apply to a range of copyright materials from 1 January 2019. For the first time in Australia, a copyright term will apply to unpublished materials (which previously had unlimited copyright protection). The result of these changes is that hundreds of thousands, possibly even millions, of theses, diaries, letters and other old unpublished works held in our national collections have entered the public domain.