There are two primary forms of citation in the Harvard style, dependent upon whether the reference is used as a noun or parenthetically. The citations themselves are in author-date style, with authors after the first suppressed in repeat citations.

The three original bibliography styles are agsm.bst (for Australian Government publications), dcu.bst (from the Design Computing Unit of the University of Sydney) and kluwer.bst (aiming at the format preferred in Kluwer publications). The author is Peter Williams.