Significant Impact brings together stories, essays, and narrative cartography in a counter environmental assessment to document and describe the effects of surveillance infrastructure on the Tohono O’odham Nation—a Native American reservation on the United States-Mexico border. A collaboration between O’odham rights advocate Ophelia Rivas, human rights scholar Nina Valerie Kolowratnik, and architectural historian Caitlin Blanchfield, the book advocates against militarized infrastructures on Indigenous lands and challenges common protocols of environmental review, along with the Western frameworks of scientific classification and property embedded in them. The project makes visible the impact of surveillance when considered through Indigenous sovereignty and an O’odham epistemology of land.