The death toll of the Rwandan genocide remains highly debatable. The frequently quoted estimate of 500,000 Tutsi killed is based on the population census of 1991. However, two unanswered questions make this estimate unreliable. First, how many Tutsi lived in Rwanda prior to the genocide? Second, how many Tutsi survived? With respect to the first question, critics say that the proportion of Tutsi was under-reported in the 1991 census. By comparing the census data with population data of the local administration of Gikongoro Prefecture, we provide evidence for this allegation and study how the under-reporting may affect the estimate of the genocide death toll. We also use local population data for 117 administrative sectors within Gikongoro Prefecture to make a detailed analysis of the spatial pattern of killings in Gikongoro. We find that Tutsi in Gikongoro had, on average, a 25% chance of surviving the genocide. The survival rate for women was only slightly higher than for men: 29% versus 21%. The location of huge massacres and the way violence spread across sectors were more decisive for the Tutsi survival rate than whether or not local authorities opposed the genocide.