This article considers the growing body of STS research on absences in technoscience. While solid conceptual ground has been made in theorizing different forms of absence and their social production, researchers have not paid sufficient attention to various methodological challenges that a focus on absences implies. How does one study what is not there? I offer 10 methodological considerations as a provisional foundation for an empirical program of research on absences and a brief illustration drawn from an ongoing study of absence in post-Katrina New Orleans.