Confusion reigns in discussions about the cost of the Department of Defence’s equipment projects. Whether we’re talking about media articles, parliamentary committee hearings, letters to the editor, duelling internet commentators or any other forms of discourse that address Defence acquisitions, the only thing that’s clear is that we’re almost always talking past each other when it comes to the cost of military equipment. Defence doesn’t help when it releases only a bare minimum of information. This sorry state of affairs reached its peak several years ago, when it turned out that when Defence said that the cost of the Attack-class submarine was $50 billion it really meant that the cost was somewhere around $90 billion.

The situation gets even murkier when commentators compare the cost of military acquisition projects here in Australia with ones overseas. It’s very rare that we can make a direct, apples-to-apples comparison between local and overseas projects, and very often it’s more like apples-to-orangutans. Being completely unaware of the basis of the costs they are comparing doesn’t stop some commentators from making strong claims about the rapacity of foreign arms companies or the competence of the Australian Defence Department.

This report attempts to be a guide for the perplexed. It’s not a technical manual, but a plain-English discussion that unpacks the cost of Australian defence equipment projects. While it would be useful for those working in the field of defence and strategic studies to read the whole report, it can also be used a reference tool explaining key terms such as ‘constant’ and ‘out-turned’ dollars or different cost-estimation methodologies.