In recent attempts to address the notion of teacher identity, scholars have stressed how identity is dynamically evolving, intrinsically related to others, and consists of multiple identities. Though these postmodern characterizations represent radically new perceptions of identity, they are not extensively discussed in relation to previous assumptions on singularity or sameness of teacher identity. The emerging theory of dialogical self in psychology offers a more elaborate approach to teacher identity, conceived of as "both" unitary and multiple, "both" continuous and discontinuous, and "both" individual and social. Based on this approach, teacher identity is re-defined and implications for research are identified. (Contains 1 figure.)