Asian primates are found primarily in the oriental biogeographical region from India to the archipelagos of the Philippines and Indonesia, including the transition zone to Australasia (Wallacea). However, species diversity and distribution patterns of primates in the mountainous transition zone of the southeastern Palearctic to the subtropic parts of the “Orientalis” are less well known and understood. This is clearly illustrated by the fact that 4 of the 16 primate species covered in the book Primates of the Far Eastern Himalaya—Arunachal macaque (Macaca munzala), white-cheeked macaque (Macaca leucogenys), Myanmar snub-nosed monkey (Rhinopithecus strykeri), and Skywalker hoolock gibbon (Hoolock tianxing)—have been scientifically described as new species only in the last 15 years, boosting the list of Asian primates up to about 120 species (cf. Mittermeier 2013). Regarding the rate of new species descriptions in primates over the past 2 to 3 decades, which is higher than in most other vertebrate orders, one could expect that this is not the end of the story, not even in the remote and rugged mountain regions of the Himalayas. Even though, in my opinion, species numbers have been somewhat artificially inflated during recent decades because of new species concepts, the increase in species and taxon numbers of primates from 275/630 (Mittermeier and Konstant 2001) to over 479/681 (Mittermeier 2013) and on to the current staggering tally of 502/716 (Rylands et al 2020) clearly shows an increase in knowledge about primates and indicates an overwhelming interest in this intriguing group of animals, not only in the scientific community but also in the general public.

Broadening public knowledge about nature and its relationships to human activities can rightfully be regarded as the most important goal of the natural sciences, and this book, given its concept and content as well as writing style and layout, is clearly designed to mainly serve such precious purposes. This release of the International Centre of Integrated Mountain Development (ICIMOD), also available in book form, is reminiscent of leaflets in the style of World Wide Fund for Nature, BirdLife, or International Union for Conservation of Nature (IUCN) publications aimed at nonprofessional customers and readers. Undoubtedly, Primates of the Far Eastern Himalaya achieves its aim. It is superbly illustrated and professionally designed, and 78 mostly close-up full-page photos of the 16 primate species make up two thirds of the 114 pages of the main part of the book, where the region's known species are portrayed. The 1-page species accounts are arranged in 4 chapters: “Loris,” with 1 species (Nycticebus bengalenis); “Macaques,” with 6 Macaca species; “Langurs,” with 2 Rhinopithecus and 4 Trachypithecus species; and “Gibbons,” with 3 Hoolock species. They offer a brief description of the species' distribution and elevational range, as well as basic information about habitats, ecology, population size, threats, and the current IUCN conservation status. Specific comments about taxonomic status and relationships as well as field marks and the history of discovery are given under the header “Narrative” at the end of each species account. For R. strykeri and H. tianxing, species that are brand-new to science, stories of their discovery and more details about their ecology and behavior are given on separate pages. The species accounts are accompanied by schematic distribution maps that show the delineation of the Hindu Kush Himalaya in the background—a helpful tool for orientation, comparison, and reference.

The introductory section of the book comprises brief notes about the aims and the scope of work of the publisher, ICIMOD, and of the Landscape Initiative for the Far Eastern Himalaya, followed by short summaries of the global and regional status of primates and their outstanding importance as flagship species for nature conservation. This latter topic is again given special consideration at the end of the book, in the chapters following the species section. The first of these is entitled “Conservation to Policy Actions: Species Discovery to Protection (China).” The final chapters deal with the role of primates in regional myths, folklore, and cultural practices, which present some challenges to conservation measures but also offer opportunities, and with the transboundary collaboration needed for the sustainable protection of nature in the region. Further, the book includes a substantial and up-to-date bibliography of relevant literature comprising 84 published and partly unpublished titles, about 70% of which make specific reference to the region's primate species. It should be emphasized that most of the literature cited has been published in the last decade, which not only indicates the rapid growth of knowledge about the region and its species, but also offers a valuable starting point for readers with a deeper interest in the primates of the remote and mountainous far eastern Himalaya.

In the foreword, Pema Gyamtsho, director general of ICIMOD, states that the book is aimed at general readers and specialists alike, which I think is a bit overstated. Given the style of writing and layout, the emphasis on beautiful pictures, and the rather coarse ecological information provided in the species accounts, it is obvious that the book is pitched primarily to a wide, nonspecialist audience and less addressed to the scientific community—which is by no means intended as a criticism per se.

From the standpoint of an advanced reader with a deeper interest in biogeography, ecology, and primate biology, a few aspects are not entirely clear and are in part unsatisfactory. To begin with, the geographic reference in the book's title, “far eastern Himalaya,” might be a bit confusing and even misleading, especially to a reader from the Western hemisphere. If one takes the traditional definition seriously, the Himalaya per se extends only from the Indus River in the west to the great bend of the Yarlung Tsangpo River (the upper section of the Brahmaputra) in the east. Although high mountain ranges continue hundreds of kilometers to the east and southeast, the transboundary region between northeast India (Arunachal Pradesh), northern Myanmar, and southeast China (Hengduan mountain chains), which is primarily meant here by the term “far eastern Himalaya,” has biogeographical, environmental, and climatic connections and conditions that differ from the Himalaya proper, and the more general term “Himalayas” instead of “Himalaya” might seem more suitable to address these differences. In any case, a more detailed delineation and description of the study region in the text of the introductory chapters, as well as in the maps, would have been welcomed. At a minimum, a general map that shows the borders and the courses of the main rivers would have been helpful. In addition, a few representative pictures showing the main primate habitats of the region and exemplifying human pressures on them would have been appreciated. Moreover, a basic descriptive overview or a few statistics, for example about land use patterns and their changes and about landscape portions of the main habitats and of the existing elevational belts, would have been useful for readers unfamiliar with this remote and little-known but fascinating region. The popular approach of the book also leads to occasional sloppy writing. For instance, the habitat of M. leucogenys, a species restricted to southeastern Tibet and northeastern Arunachal Pradesh, is incorrectly denominated as “tropical” forests.

Such, possibly a bit puristic, technical remarks, however, cannot cast any doubt on the fact that this ambitious book is commendable and will indeed serve its main purpose—to inspire readers with the beauty of primates, and to raise the awareness of decision makers and the public of the threats that these iconic animals are facing and of the need to increase conservation efforts.