It's the uncertainty that is the hardest to bear. The passage of time brings no relief from the anguish or the anger. On 30 August, the International Day of the Disappeared, we remember those who have been abducted, held in clandestine places of detention, tortured and, in some cases, killed. We pay tribute, too, to the courage of families kept in the dark about the fate of their loved ones. Let's also take this opportunity to reflect on how enforced disappearances can be prevented in the future.

Enforced disappearance is a crime under international human rights law and – when it occurs in war – under international humanitarian law. It is tantamount to deleting a person's very existence and denies him or her the basic protection of the law to which every man and woman, irrespective of guilt or innocence, is entitled. It is a violation of that person's rights and the rights of his or her family. The damage to the bereft, who, unlike the bereaved, continue to hope against hope, is far-reaching and long-lasting, affecting not only individuals but the societies in which they live

Sadly, State-ordered or -supported abductions, secret detention and extrajudicial killings are nothing new. These crimes have been committed repeatedly on all continents throughout history, and continue to be committed at this moment. According to the United Nations, some 50,000 enforced disappearances have been reported since 1980 in more than 90 countries around the world. Last year, the UN Working Group on Enforced or Involuntary Disappearances asked governments to investigate over 550 new cases.

And yet few of those responsible for these acts have ever been held to account. Impunity or failures of justice create a social climate in which there can be no trust in institutions and hence no stability. If enforced disappearances go unpunished, the memory of the missing will haunt the societies in which such acts are covered up.

Families of the disappeared around the world have fought against such impunity for many decades. They have kept the memory of their relatives alive by demanding answers, while at the same time working to prevent future disappearances. One part of their struggle has been a growing demand for an international treaty.

After 25 years of campaigning by families, the new UN Human Rights Council approved the International Convention for the Protection of All Persons from Enforced Disappearance on 29 June 2006. The treaty will now be submitted to the UN General Assembly for adoption by the States. The new Convention contains an absolute prohibition on enforced disappearances in both peacetime and wartime. It also stipulates that no person can ever be placed beyond the protection of the law. It obliges States to make enforced disappearance a crime and enshrines measures such as the registration of detainees, their right of access to a court and the right to contact their lawyers and families. Importantly, it establishes an international mechanism to supervise States' compliance with their obligations under the Convention, and an urgent appeals procedure that can be used where enforced disappearance is suspected.

Pessimists may say that this is just another convention and that it will not suffice to combat enforced disappearances. But, over the years, we have seen the development of international humanitarian law and international human rights law gradually exert a positive influence that no one would have dared to imagine 50 years ago. Explicitly regulating the rights of individuals and the obligations of States helps to draw clear boundaries between the rule of law and arbitrary acts.

International supervisory mechanisms also have an impact. At the first session of the new UN Human Rights Council in June 2006, the foreign minister of Chile, Paulina Veloso, whose husband disappeared in "Operation Condor" in 1977, gave testimony in which she expressed her belief that the UN's efforts on behalf of the disappeared, together with general condemnation by the international community, produced a dissuasive impact which may have limited the number of disappearances. "At those moments of loneliness and anxiety", Mrs Veloso told the Council, "the care of the Commission was a great support to me, which gave me strength to keep confidence in people, in human rights and in the community that defends them."

The International Committee of the Red Cross works tirelessly to try to stop enforced disappearances. For the ICRC, the strongest safeguards against people going missing in armed conflicts are repeated visits to detainees and the work done to restore and maintain family links. Last year, ICRC delegates visited about 2,500 places of detention in some 70 countries, visits that benefited some half a million detainees. They also followed up on more than 46,000 detainees who had been previously visited and enabled some 100,000 personal messages to be exchanged between detainees and their loved ones.

Families' quests for answers and their efforts to keep alive the memory of those who have gone command our admiration and respect. Their persevering struggle to repair the injustice done and to prevent such acts from happening again elsewhere deserves support from the community of States and the public at large. This new Convention will introduce sorely needed measures to prevent enforced disappearances in the future. It should therefore be swiftly adopted by the UN General Assembly and ratified by a large number of States.

See also The Missing: ICRC Progress Report.