Understanding how defects can affect ground-state properties, promote phase transitions, or enable entirely new functionalities in some strongly correlated oxides has become a subject of major interest in the field of design and discovery of novel functional materials. SrMnO3 (SMO) is a particularly interesting example, but better characterization is needed. MARVEL researchers have now a developed a method that may lead to more accurate predictions of the energetics of defects associated with in-gap states in semiconductors or insulators.