This study examines organizational commitment’s potential role as a psychological mediator between the relational conditions in schools and individual teachers’ intentions to leave their positions. Although there is a wealth of evidence testifying to the importance of working conditions in teachers’ turnover decisions, there has been little discussion of the explicitly relational nature of the most salient working conditions identified in the literature—conditions like collegiality, collaboration, mentoring, student discipline issues, and perceived administrative support. Furthermore, there is often a lack of theoretical explanation for why certain conditions result in turnover; the psychological mechanisms at play within teachers are not well understood. Self-determination theory provides a lens through which working conditions can be analyzed—as either supportive of or frustrating teachers’ innate psychological need for relatedness. Support is found for the idea that positive relational conditions within schools reduce turnover intention, mediated through their effects on teachers’ feelings of organizational commitment.