This year-long ethnographic case study examined high school teachers' participation in technology-focused professional development. By pairing a dialogical perspective on teacher identity with a micro-level analysis of narratives, findings indicate that teachers use language and other semiotic resources to express their own identity as well as to acknowledge, expand on, and counter others' identity claims. Moreover, technology integration may challenge teachers' established identities or threaten their authority in the classroom. This analysis suggests that teacher educators need to value teachers' established and emergent identities as well as create space for dialogic narratives in order to facilitate technology integration in schools.