Drawing from social-ecological systems theory, the authors argue that current research on childhood bullying would benefit from analyses that consider the mesosystem--specifically, how teacher-student relationships can influence children's bullying experiences. The authors provide two theoretical conceptions for how children's peer interactions are implicitly shaped by teacher-student relationship quality: attachment and social referral. Implications for practice, with an emphasis on developing teachers' social-emotional competencies to strengthen positive teacher-student relationships, are proposed.