ON New Year's Day, Sir Craig Reedie takes over as president of the World Anti-Doping Agency.

It is arguably the most challenging job in world sport. Probably Britain's most powerful sporting figure, Reedie has a peerless curriculum vitae, yet was dismissively introduced by Jeremy Paxman who asserted recently that the new head of WADA is "a 72-year-old former badminton player from Glasgow".

That may be more of a comment on Reedie's smooth, self-effacing diplomatic style than on sloppy research of Paxman's brief. Or simply contrived for dramatic effect. Suffice to say, you don't get a CBE and a knighthood for services to sport for mopping sweat droplets off badminton courts.

Sport is battling for its soul and its future. Is WADA under Reedie up to the job? We had better hope so, for it would be hard to find a comparable alternative.

From Bridge of Weir, Reedie was once Scottish doubles badminton champion and an international player. The law graduate's subsequent off-court career has been more high profile. Former secretary, treasurer and president of Scottish Badminton and then head of the world governing body, he played a fundamental role in the sport achieving Olympic status.

He chaired the British Olympic Association through six Summer and Winter Games, was a key figure in winning 2012 for London, and a director of its organising committee. He was deputy chair of UK Sport and a member of the Lottery distribution board. He has been a member of the International Olympic Committee since 1994 and is now a vice president, having served on numerous commissions as well as chairing the one which evaluates candidate cities.

Formerly senior partner with a Glasgow firm of financial advisers, he has been with WADA since its inception 14 years ago. He was voted president last month in Johannesburg where a new anti-doping code (coming into force 12 months from now) was ratified from a list of 4000 proposed amendments. "This," he says, "is the last big job".

He has just returned from Montreal and a meeting with WADA staff but, having devoted his life to encouraging people to adopt, promote and play sport, the switch to head prevention and enforcement officer is a culture change.

It is a war sport cannot afford to lose, and omens are not encouraging. Richard Pound, the inaugural WADA president and a fellow IOC member, this year delivered a damning critique. He said WADA's test system was less effective than it should be and suggested a lack of concerted will was conspiring to beat the system.

Lance Armstrong's serial Tour de France cheating and the 167 tests passed by the Olympic gold-medal sprinter Marion Jones, make it hard to disagree. "We have discussed that," said Reedie, who succeeds the Australian politician John Fahey at WADA. "Coming from the sport side, I want to re-energise international federations and the IOC, in making sure they understand this battle has to continue and that we must keep making progress. If we don't, sport is not going to be worth a damn. Youngsters will not want to take part in sport and those who watch and enjoy sport will question its validity. That's not a happy scenario.

"[There has been] strain between some agencies and WADA in the past few years, in the main personality driven, which is the most difficult thing to fix. It's not particularly process-driven and I need to fix that. So I see my role, initially, being diplomacy."

This seems a veiled reference to a defamation action between Pound and Hein Verbruggen, then the International Cycling Union chairman and IOC member, which undermined goodwill. Reedie declines to discus it but, with Verbruggen's successor, Pat McQuaid, having been ousted this year, and Reedie's predecessors [Pound and Fahey] both hinting that cycling risked Olympic exclusion if it failed to clean its house, bridges clearly need rebuilt. This will test all of Reedie's diplomacy skills.

"The new cycling regime is determined to establish an independent inquiry, and has asked WADA for advice and guidance which will be happily given," he says. "If cycling wishes to look at what has happened in its past, that's their issue, but I'd rather move on. WADA's job is not to sort out sports. It's up to a sport to sort itself out.

"We all need to sing off the same hymnsheet, work together more and be smarter. The new code is huge progress. The move to higher sanctions for serious cases is a good one. The athletes of the world, particularly when they spoke in Johannesburg, were outstanding on that. Thomas Bach [the new IOC president] stressed how we are in the business of protecting the clean athlete. One way to do that is higher sanctions. The four-year penalty will remove a sinner from the next Games and is now enshrined in law."

This is a personal coup. The BOA championed the four-year ban only for it to be dismissed as double jeopardy. Now it will be the norm.

He applauds the adoption of sanctions against coaches and medical support involved in doping, and the extension from eight years to 10 of a statute of limitations on bringing defaulters to book. "I think it's right that medals should be reallocated: a real deterrent."

He welcomes the possibility of a reprimand rather than automatic suspension if an illegal substance has been innocently ingested. "This will give athletes more confidence in the system. It's realistic and fair," he insists.

A total of 174 nations ratified the UNESCO convention. "Now, we hope all 174 will implement it. Sport would be very grateful if governments would actually put in place the legislation, regulations, or administration policies to allow information-sharing."

I suggest that making steroid possession without prescription a criminal offence would help, but he is "not certain".

"Criminalise trafficking and dealing, yes, but I don't necessarily want sportsmen in jail for doping offences. I just don't want them competing in sport."

He says he needs to raise money. WADA's 2014 budget is lower than £30m; less than the income of many individual elite competitors, far less international sport federations.

Do Pound's criticisms have substance? "WADA were slow in actually reacting to some of them," he concedes. "Dick has encyclopaedic knowledge and is famously critical. There is nothing wrong with that and a lot of what he has said has been implemented in the new code.

"If current routine urine-based testing is insufficient, we have to do something about it. Hence plans for new sport-specific testing venues, the increased development of blood passports and a steroid module based on urine samples. Any informed criticism, I am quite happy with."

I suggest that, with one foot in the IOC, and the other in WADA, he could face conflict of interest. I cite Crystal Cox, the US athlete who ran in the Athens Olympic 4 x 400m heats, was suspended after an admission to having doped that year and stripped of her gold medal, yet the rest of the US quartet kept theirs. The GB squad, including Scotland's Lee McConnell, were fourth.

Surely justice demands the US be disqualified, with Great Britain upgraded to bronze. Does WADA not experience discomfort at Olympic gold going to athletes who are not entitled? A known cheat helped to win gold and the Olympic movement is not correcting it?

"WADA is not involved in that at all," says Reedie. "The issue is between the IOC and IAAF. The IOC says a statute of limitations is involved and the matter is closed. The difficulty was ascertaining when the doping offence actually took place and what rules were then in force. Penalties are determined by the international federation and the statute of limitations is well past.

"Was an offence committed? Yes. There is a set of penalties that come into place. As far as the IOC is concerned it is only involved in medal distribution. Penalties are decided by the international federation. We, as an organisation, would leave that to the responsible stakeholder to deal with. That's the IOC for the Olympics and the IAAF for its own rules. "

I suggest that the BOA will not let this go. He replies that he "looks forward to being on the IOC executive board when it is discussed".

No conflict of interest? "Not in this particular case, because WADA has no medal-granting authority at the Olympic Games and no authority to decide which rules applied for the IAAF. So I won't have a conflict of interest if and when it does arise.

"This is inherent in the system. If sport has the authority to nominate the presidency of WADA and that person happens to be a senior member of the IOC, clearly there is a potential for conflict of interest to arise and I will have to deal with that."

He then revealed the depth of his commitment to the cause. "I am going to come off all of my IOC commissions: I will no longer be on programme or marketing and I certainly will come off the ethics commission. I am trying to be as neutral as I possibly can.

"WADA has done much good: the introduction of a global code; the Unesco convention; $60m invested in research. It is enshrined in countries' legislation and in all rules for sport competitions. We can't walk away from this. We have to make it work, and work better, and that's what I aim to do."

For all his remarkable achievements - the presidency of the IOC may not have been beyond him - Reedie's role at WADA may yet be what defines him.