English Language Teaching (ELT) materials, particularly textbooks, constitute pivotal components in the English language classroom as they facilitate effective English language learning and teaching, thereby immensely influencing the quality of English language education. Even though the literature and previous research recognize the significance of locally developed materials and advocate for producing more localized ELT materials and texts, global ELT textbooks by international (particularly British) publishers take precedence over home-made materials in the vast majority of ELT contexts worldwide. This chapter sheds light on some prominent criticisms of the preponderant global ELT textbooks and underscores the need to adopt the Teaching English as an International Language (TEIL) paradigm and glocalize ELT materials for effective English language teaching and learning in local contexts. Furthermore, it presents a materials development framework as well as an overview of a newly designed training module for English language teachers, representing some of the authors’ ambitious proactive endeavors toward guiding and enabling local professionals to glocalize ELT materials in Malaysia. The chapter concludes with significant implications for ELT materials development and training English language teachers in Malaysia and comparable settings that seek to teach English as a global language.