This chapter systematically reviews empirical studies on good language teachers (GLTs) published in peer-reviewed journals between 2010 and 2020. The review seeks to examine the primary research aims, methodologies, profiles of participating teachers, and their teaching contexts and synthesizes relevant key findings from the GLT literature. To fulfill these aims, a comprehensive search of Scopus and Web of Science databases was conducted, yielding 62 studies that met the inclusion and quality assessment criteria. The review shows that the main research aims were to explore stakeholders’ perceptions of GLT characteristics, factors related to teacher effectiveness, and the development and assessment of teacher expertise. Interestingly, studies employed a balanced mix of quantitative, qualitative, and mixed methods approaches. Based on the findings, the chapter proposes a model of language teacher expertise comprising three core domains, namely attributes, knowledge, and contextual adaptability, to underscore the multifaceted nature of language teacher expertise and highlight the importance of both intrinsic qualities and situational factors. The chapter concludes by suggesting a holistic approach for language teacher education programs, outlining the limitations of the review, and making recommendations for future GLT research.