Twenty-one agencies responded to the request for proposals, issued in October, and the IAB has since whittled down the applicants to a shortlist of Nielsen Online, ComScore and ViziSense, plus two joint bids from Roy Morgan Research and Effective Measure and Colmar Brunton and Gemius.

IAB chief executive Paul Fisher (pictured) said: “We’re very pleased with the industry credentials of the tendering companies and the breadth and calibre of responses. The culmination of this extensive and rigorous process will be the most significant single event in online audience measurement in Australia.”

The five submissions will now be reviewed by the IAB’s technical group, chaired by media researcher Ian Muir and including measurement experts from the IAB Measurement Council, the Media Federation of Australia and the Australian Association of National Advertisers. The winning company will be named as the IAB’s preferred supplier of web audience data for a three-year period.

Australia already has one web measurement auditing system in place, provided by the Audit Bureaux of Australia who teamed up with Nielsen Online to launch the service in 2009. ABA chief executive Gordon Towell did not welcome news of the IAB’s audience measurement plans, remarking at the time that: “If research methods are audited, any number of companies could provide the audience figures and they’re all comparable – you don’t need to have one company doing it all.”