The Australian Science Fiction Achievement Awards, or Ditmars, are awarded by Australia's National Science
They are named after Dick "Ditmar" Jenssen, a fan from Melbourne. Awarded annually, they have, at various times
Fiction Convention, and are voted on by members of that convention. They are thus a popularity award representing
the choice of Australian science fiction fandom.
in their history included international categories, but in later years all categories became open only to Australian work. Categories include both professional and non-professional work that focusses on fiction, but also includes other
categories. The William Atheling Award is an award for works of criticism or review that is also awarded as part of the same
process. The trophies traditionally have proportions approximating the monolith from the film and novel 2001: A Space Odyssey
(1x4x9) and include a motif of the southern cross constellation. The inaugural Award was conferred in 1969 for work published in 1968. Altogether there have been thirty-five Conventions at which the awards have been conferred.