This article reported how five preservice teachers constructed and developed their teacher identity in a year-long teacher residency partnered between a university-based teacher education program and schools in Louisiana, United States. Drawing on a sociocultural approach to identity development and the 'third space' theory, qualitative data were collected from individual interviews, classroom observations, and document analysis. Findings suggested that participants experienced an ongoing teacher identity construction while learning to teach in the hybrid, in-between 'third space' residency. Key elements of the residency, including the mentored co-teaching experiences and learning opportunities situated in authentic school contexts, facilitated the participants' learning about teaching and teacher identity negotiation. Implications for teacher education practice, policy, and research were discussed.