We explore the phenomenon of status disagreement in groups, which occurs when two group members both believe they have higher status than each other. Across two studies, we investigate the consequences of status disagreements for group performance and group member behavior. In Study 1, we incite status disagreement in groups working together in the laboratory, and analyze members’ behavior using detailed observation from videotape. In Study 2, we observe naturally occurring status disagreements in group of students working on a longer-term class project, and employ Hierarchical Linear Modeling and the Social Relations Model (Kenny & LaVoie, 1984) for behavioral analyses. In both studies, we find a negative association between status disagreement and group performance. Further, analyses of group member behavior indicate that this relationship is primarily due to reduced contributions by individuals engaged in status disagreement. These findings speak to the importance of status disagreement for group dynamics and suggest that purely cooperative conceptions of status differentiation may be incomplete.