This course explores major issues related to the global spread of English and their implications for language teaching. We will examine foundational concepts such as World Englishes, English as a Lingua Franca (ELF), and native-speakerism, while also addressing the ideological and pedagogical roles of non-native English-speaking teachers. The course then moves into practical applications, exploring how to design and implement lessons and tasks informed by the principles of Global Englishes (GE). We will critically analyze the use of English in teaching materials and discuss how to adapt them to be more inclusive. We will also focus on specific pedagogical areas, such as teaching pronunciation from a GE perspective, and contemporary topics like the role of AI in language teaching. Throughout the course, students will be encouraged to explore possible research directions related to Global Englishes and to reflect on their own beliefs and potential roles as future English teachers in a globalized world.