The continuation of English's current dominance as the world's lingua franca may seem unquestionable, but Nicholas Ostler's new book challenges this commonsense view by arguing that English may be the last lingua franca. The author discusses how it is so by reviewing language histories from the ancient to the present as well as predicting the future based on current language technologies. The book consists of four parts with twelve chapters. Chs. 1 and 2 in Part 1, “Lingua-franca present,” trace the development of English as a lingua franca, paying particular attention to diversity in English use in past British colonies. Ch. 2 stresses the importance of distinguishing mother tongue from lingua franca, because only the former tends to be transmitted to each new generation. Chs. 3–6 in Part 2, “Lingua-francas past,” examine the wax and wane of major lingua francas in western and southern Asia based on reasons for their spread. Chs. 3 and 4 discuss Persian as an example of a lingua franca for military empire-building. Ch. 5 examines lingua francas that were developed for networks of commercial enterprise, such as Phoenician, Greek, Sogdian, and Chinese. Ch. 6 reviews languages used for the propagation of religion, mainly Sanskrit and Pali for Buddhism and Latin and Aramaic for Christianity. Although these languages attained the status of sacred languages, missionary English has kept its secular status. Ostler argues that Protestant Christians' support for vernaculars has made this difference, and he also conjectures that this “will contribute to a possible global shift away from universal lingua francas in the modern world” (169).

Chs. 7–9 in Part 3, “A range of outcomes,” discuss the extinction process of the past lingua francas based on the manners of their breakdown: ruin, relegation, and resignation. Ostler defines ruin as “the downfall of an economic network,” relegation as “a political act, summarily ending an official status,” and resignation as “the most diffuse of the three, a social trend that undermines and demeans the position of a previously respected elite” (183). After discussing regeneration processes of lingua francas in Ch. 7, Ch. 8 discusses ruin and relegation, and Ch. 9, resignation.

Lastly, Chs. 10–12 in Part 4, “Who's in charge here?,” explore the future. Ch. 10 examines the current twenty-five most widely spoken languages in the world, paying attention to these languages as mother tongue and lingua franca. Reviewing information on technology development, Ch. 11 points out that information technology may undercut the necessity for a lingua franca. Finally, Ch. 12 explores several possible outcomes for English and predicts that by the middle of the twenty-first century further development of translation technology will enable direct global communication using the speakers' vernacular possible without the aid of a lingua franca. Ostler's colorful world language career—study of Latin and Sanskrit, research and teaching in various countries, activities to save endangered languages, and machine translation projects for an EU commission—is synthesized and crystallized in this book, making his seemingly provocative thesis convincing.