Purpose: This study examines the relational dynamics between teachers and formal teacher leaders (TLs). We examine the association between relationship structure and leader-member exchange (LMX) quality and the extent to which LMX mediates the relationship between social network (SN) measures of dyadic relationships and TL influence. Design/methodology/approach: Using survey data from 1,895 teacher-TL relationships, we employ path mediation analysis using hierarchical linear modeling. Findings: Our results indicate that voluntary advice-seeking and multiplex ties are associated with stronger exchange quality between teachers and TLs. In addition, LMX partially mediates the relationship between voluntary ties and TL influence. Originality/value: SN and LMX theories offer two complementary lenses for studying relational dynamics in organizations, though they seldom are used together, especially in education. This study bridges SN and LMX theories and measures to bolster studies of relational dynamics in organizations and highlights that in the case of formal teacher leadership, there is a need for school structures that enable teachers and TLs to seek out one another informally and develop strong social exchanges. [For the corresponding grantee submission, see ED614519.]