This descriptive study used an online survey to determine how principals in two states viewed the supervision of marginal teachers. Principals ranked their own evaluation of the teacher as the most important factor when identifying marginal teachers and relied on informal methods to diagnose marginal teaching. Female principals rated a majority of supervisory methods and data sources as being more useful and the importance of formative assessments and teachers' self-reflection as significantly more important than did male principals. Female principals adopted a procedural style, while males identified with the situational style when working with marginal teachers.