The mass murder of the European Jews by Nazi Germany went hand in hand with the destruction of evidence attesting to this genocide. As Holocaust survivor Jules Schelvis puts it, "[v]ery few documents relating to Sobibor and the other death camps" remain. With its rich photographic imagery, the collection featured in From "Euthanasia" to Sobibor: An SS Officer's Photo Collection sheds new light on the Holocaust and other key aspects of Nazi extermination policy. The materials were compiled by Johann Niemann, an SS officer whose earlier participation in the Nazi "euthanasia" murders made him second-in-command at Sobibor and the first to get killed in the prisoner uprising of October 13, 1943. These documents allow crucial insights into the making of mass murderers, the evolution of the "final solution," and its consequences for the victims. As prevalent as the perpetrator perspective is in Niemann's collection, From "Euthanasia" to Sobibor offers a welcome corrective by complementing his images and documents with testimonies of Sobibor survivors, many of which also available in the US Holocaust Memorial Museum (USHMM) archives. With its compilation of unique primary sources and skillful explication, From "Euthanasia" to Sobibor addresses under-researched aspects of Nazi mass violence beyond the Holocaust and offers a rich resource for researching and teaching.