Chambers may never again run in the Olympics
Dwain Chambers' 'B' sample has confirmed his positive test for the banned anabolic steroid THG.
So what happens now?
Usually drug tests on British athletes are conducted by UK Sport, and the results then passed on to UK Athletics, the sport's national governing body.
But Chambers' test was authorised by the International Association of Athletics Federations, so it is the IAAF who have been dealing with the early parts of the case.
With both 'A' and 'B' samples positive, the IAAF will now contact UK Athletics and advise them that Chambers should be suspended immediately.
UK Athletics' board then convenes a hearing by an independent disciplinary committee, which is made up of three people - one with a legal background, one with a scientific background and one from the athletics community.
It can take as little as four weeks or as long as six months for the hearing to take place, depending on the complexity of the case to be presented.
During that time Chambers would continue to be suspended from competition.
Chambers and his legal team will be given every opportunity to put together a full defence, even if this means the hearing does not take place until well into 2004.
The defence might wish to bring forward new scientific evidence or mitigating circumstances, while the panel hearing the case has the scientific reports from the test and any statements Chambers may have made in the interim.
Chambers faces a two-year ban if found guilty
The hearing itself is a confidential process, so in theory we will not know the identity of the panel, where the hearing is being held or the nature of the evidence presented.
Generally such hearings take no more than two days and are often wrapped up in one.
The panel then retires to consider their verdict and write up a report.
If Chambers is found guilty of taking a banned steroid, he would be given an automatic two-year ban from competition.
The ban would start from either the date of the test or the date Chambers last competed, whichever was later.
As the test in question took place on 1 August and Chambers' last competitive race was in the Moscow Challenge on 20 September, he would find himself banned by UK Athletics until 21 September 2005.
Before Chambers could be selected for a British team after that date, he would need to run the qualifying time for his event again. A qualifying time has to have been run no earlier than a year before selection.
If a positive test was confirmed, the British Olympic Association would ban Chambers for life - meaning he could never again take part in an Olympic Games.
And a positive test would also make Chambers ineligible for National Lottery funding from UK Sport's World-Class Performance programme.
At the moment it seems unlikely that UK Athletics will launch their own inquiry into THG (tetrahydrogestrinone), but Chambers could also be asked to give evidence to any subsequent IAAF inquiry.
Chambers does have the right to appeal against the hearing's verdict, at the Court for Arbitration in Sport, which is based in Lausanne, Switzerland.
Both the athlete and disciplinary panel will agree in advance of the hearing to stand by any judgement that the CAS makes.
Chambers could, however, take his case to the European Court of Human Rights if he still feels he has been wronged.