Clothier, one of Australia's leading sport integrity professionals, fills the final position on the AIU.

He replaces Thomas Capdevielle who filled the position temporarily until a permanent candidate was found.

Clothier established and led the Australian Football League (AFL) Integrity Unit for more than eight years, tackling doping alongside match-fixing and other issues.

Prior to his role at the AFL, Clothier spent four years as legal counsel to the Integrity Services Department of Racing Victoria, the Australian state's principal horse racing authority.

"Athletics is one of the few genuinely global sports," said Clothier.

"Through the AIU it has an unparalleled opportunity to demonstrate leadership on integrity issues and to share those with other sports and Federations.

"I am excited by the opportunity I have been given to lead the AIU in rebuilding athlete and fan confidence in how we manage threats to the sport.

"I look forward to working with athletes and all members of the athletics community."

It was also revealed today that Ben Nichols, the former chief spokesman at the World Anti-Doping Agency (WADA), has been hired by the AIU as its communications consultant.

He will be based in Britain. 

The AIU has been set up in response to the corruption scandal involving former International Association of Athletics Federations (IAAF) President Lamine Diack.

He was allegedly involved in a scheme to blackmail Russian athletes to avoid suspension following positive drugs tests.

It is claimed the AIU will be an independent organisation with responsibility for the management of all aspects of the anti-doping programme for international-level athletes and support personnel, as well as for the management of all other integrity-related programmes.

Clothier joins New Zealand's David Howman, who chairs the Board, France's Marc Peltier and Canadians Andrew Pipe and Abby Hoffman.

Howman was in charge at WADA when they launched an Independent Commission, chaired by its former chairman Richard Pound, which uncovered evidence of state-supported doping in Russian athletics.

The revelation led to the suspension of Russia from the IAAF in November 2015.

The country missed last year's Olympic Games in Rio de Janeiro and are also set to be barred from this year's IAAF World Championships in London. 

Capdevielle, meanwhile, will return to his duties as the Unit's deputy head and the legal and cases manager at the IAAF.

In the role Clothier will be responsible for the operations of the Unit, and for overseeing its core activities, including testing, intelligence, investigations, compliance, case management and education.

"The Athletics Integrity Unit sits at the epicentre of the IAAF’s integrity reforms and today’s announcement is the final brick in athletics' robust wall of ethical defences," saidIAAF President Sebastian Coe.

"The AIU Board’s appointment of Brett Clothier completes an impressive line-up of world renowned talent in the field of sport integrity who will be the guardians of athletics' ethics.

"The unit, which has been built for athletes so that they have the necessary information and support to make the right choices in their careers, is about restoring trust in competition.

"Brett’s experience will be a huge asset to the AIU in safeguarding our sport’s ethical credibility and I wish him and his team the very best for their vital work."

In a letter addressed to athletes, Howman warned the body will be "relentless" in their pursuit of athletes who cheat and claimed the organisation's establishment will be a "defining moment" in the future of the sport.

He said the AIU's remit is not solely focused on doping and outlined the responsibilities of the AIU, including "stamping out any and all forms of corruption and ethical misconduct within the sport".