This article examines the representation of the memory of the Cambodian genocide in the Tuol Sleng Genocide Museum in Phnom Penh. The museum is housed in the former Tuol Sleng prison, a detention and torture centre through which thousands of people passed before execution at the Choeung Ek killing field. From its opening in 1980, the museum was a stake in the ongoing conf lict between the new Vietnamese-backed government and Pol Pot's Khmer Rouge guerrillas. Its focus on encouraging an emotional response from visitors, rather than on pedagogy, was part of the museum's attempt to engender public sympathy for the regime. Furthermore, in order to absolve former Khmer Rouge members in government of blame, the museum sought to attribute responsibility for the atrocities of the period to a handful of 'criminals'. The article traces the development of the museum and its exhibitions up to the present, commenting on what this public representation of the past reveals about the memory of the genocide and the changing political situation in Cambodia.