We wish to inform you that tomorrow we will be killed with our families

This book concerns what happened when the Rwandan government in 1994 implemented a policy that called on everyone in the Hutu majority to murder everyone in the Tutsi minority. Though the massacres were low-tech - done largely by machete - they were carried out at dazzling speed, and 800,000 people were killed in a hundred days. Pastors in one Tutsi community sent a letter to their church president, a Hutu, that included the chilling phrase that gives Philip Gourevitch his title.

Mr. Gourevitch's haunting work is not only an anatomy of this genocide and what Rwandans call its "genocidal logic," but a vivid history of the background to the tragedy and an unforgettable account of its aftermath: the mass displacements, the temptations of revenge and the quest for justice, the replacement of elites and the plight of survivors, the impossibly crowded prisons and militant refugee camps.

His intimate portraits of Rwandans in all walks of life as they cope with the psychological and political challenges at survival make their tragic situation unexpectedly immediate and familiar; his narrative also shows how resurgent genocidal forces threatened to plunge central Africa into total war and how this sparked the drive to oust Mobutu from power in the Congo.

Lastly, he contrasts the Rwandans' provocatively original political response to the horror with the wholly inadequate reactions of international humanitarian organizations and foreign governments - not least the United States.