Diversity is the cornerstone of human civilization, which lays foundation for future progress in our society and education. Language policy in superdiverse Indonesia not only mirrors Indonesia's history but also echoes cultural integration in academic study. Zein's book offers a holistic perspective that is reflected in the interaction between language history and language ecology (chapters 1 and 2). The author then furthers discussion on different branches of languages, such as indigenous languages based on regional diversity and heritage and sign languages with distinct features. By analyzing ‘objectification of language’, the book sheds light on how language policy, when improved and modified, can energize a society. Chapter 3 is an introduction to the strategic design of diverse Indonesian languages. In addition to the endogenous change of language itself, Indonesia has shifted its focus to its rising international status. This has given rise to a problem—what kind of language will flourish when language varieties may not be promoted and maintained at the same level? It is natural for the central government to tip the balance, but identifying priorities and setting co-official status can help to a larger extent. As the internationalization of diverse Indonesian language is made clear by the author, the adjustment of language policy towards a globalized world is worth reconsidering.

Chapter 4 focuses on corpus planning and introduces three most prominent aspects: orthographical standardization, terminological expansion, and grammatical standardization. They deepen the social function of language diversity and give more micro perspectives. Moreover, the role of Badan Bahasa, a planning agency of Indonesian languages, is also highlighted by the researchers’ contribution to academic study. By critically considering the top-down policy of the New Order, the author leads us to the effectiveness of related language research in this special period. Chapter 5 is enlightening for future research because the author has proved to us that revitalization policy is not a single process that can stand for a long time. Instead, it needs assistance from multiple aspects, such as language speakers and entrenched inequality. The suggestions in chapter 5 are based on an in-depth study of Indonesian society and challenges it now faces. Documentation of linguistic corpora and research into language behaviour are innovative initiatives as they reveal the changing pattern of different languages better. The management of education in chapter 6 witnessed the reduced hours for English acquisition in The Revised Curriculum of 2013 from 4×45 to 2×45 minutes/week. In the next section, Zein pays close attention to how language policy, as a subject or as a way of instruction, is implemented to cement its position and guide students with certain social and cultural values. This calls for an integrated education plan as well as individualized proposals, as the author suggests.

Overall, this book, at macro and micro levels, creatively contributes to linguistic research and policy-making under multicultural contexts, and it can also shed new light on the educational development of an emerging Indonesia.