Teacher agency, considered as an element of teacher identity, has become a concept upon which studies have elaborated recently. However, academic research studies on this concept carried out in Turkey is highly limited. Indeed, there is not a consensus even on the Turkish equivalent of the concept. In this study, in which "öğretmen etkenliği" is adopted, the issues of Turkish meaning of teacher agency, its relation with teacher identity, emergence of the concept and its definitions, its theoretical foundations, characteristics of agentic teachers, related areas of research such as educational changes and professional development, and research studies on teacher agency carried out in Turkey are elaborated on based on an extensive literature review. In addition, in the conclusion, how teacher agency can be developed is discussed in the contexts of arrangement of teachers" work contexts, in service training and pre-service teacher education. With this study, it is aimed to offer a comprehensive source about teacher agency in Turkish to form a basis for future studies to be carried out in Turkey.