May 20 marks the annual Day of Remembrance for the Khmer Rouge genocide. From 1975 until 1979, Cambodia experienced one of the worst genocides of the 20th century, during which around 1.7 million people perished through systematic mass murder, starvation, disease, and forced labor – one quarter of the population. As Phay Siphan, spokesman for Cambodia's Council of Ministers, said, "We commemorate this national day so that we, the Cambodian people, will never forget the genocide committed by the Pol Pot regime, and to prevent genocide from ever happening again in our country or elsewhere in the world." This year's Day of Remembrance overlaps with the ongoing proceedings of the Extraordinary Chambers in the Courts of Cambodia (ECCC), a special Cambodian court that receives international assistance through the United Nations Assistance to the Khmer Rouge Trials (UNAKRT). Since 2008, the court has issued five indictments and one conviction – that of Kaing Guek Eav, commandant of the Tuol Sleng prison, for crimes against humanity relating to more than 15,000 deaths. As we remember the victims of Khmer Rouge, the Auschwitz Institute for Peace and Reconciliation acknowledges the important work of the ECCC and similar structures for justice. A history of unaddressed mass atrocities can hinder the achievement of development and security goals in post-conflict states. It is for these reasons that the Auschwitz Institute's Raphael Lemkin Seminar for Genocide Prevention stresses the importance of transitional justice. "Commemorative events are important markers for collective memory in the rebuilding of the national psyche and the reestablishment of social trust in a post-conflict state," said AIPR Academic Programs Director James Waller. "AIPR joins the Cambodian community as it remembers, memorializes and heals from the tragedy of 1975 – 1979. Their Day of Remembrance is not simply a commemoration, but a reminder of our shared mission towards the prevention of genocide and mass atrocities."