The Last Speakers is an engaging and thought-provoking treatment that reports on the extinction crisis that threatens many languages worldwide. Through photos, graphics, short vignettes, interviews, and first-person stories, this scientist's notebook documents linguist K. David Harrison's around-the-world adventures to meet with last speakers of languages. The speakers' points of view are revealed through candid direct quotations and captivating photographs that capture the individuals not simply in static poses, but in active engagement with their environment and their traditional and modern lifeways. Writing in a personal journalistic style, Harrison details his travels to visit language hotspots around the world - an undertaking also chronicled in the recent film The Linguists. Working with other professionals, photographer Chris Rainier, and local scholars, Harrison ventures to remote corners of Bolivia, Australia, Siberia, Japan, and India. There he seeks out any speakers of languages previously reported as extinct, and tries to clarify numbers of speakers for very small languages. The Last Speakers clearly explains the new, cutting-edge methods in social science that the team employs, as well as summaries of well-established (yet not widely known) scientific knowledge in the field. Languages don't disappear only in tiny hamlets. Harrison also visits last speakers living in urban areas in the developed world, to demonstrate that language extinction is happening, though largely invisibly, right in our own backyard. Sites include Oklahoma, Wisconsin, Japan, and several European nations. At some of these locations we observe focused efforts at language revitalisation, including the use of computer and internet technologies to assist small languages in bridging the digital divide. Ultimately, Harrison's book humanises the global language-extinction crisis. Last speakers eloquently discuss their feelings about their language, what will be lost if it goes extinct, and how and why they believe this loss is happening. To prevent extinction of these cherished words and meanings, some speakers actively participate in language revitalization programs, working to pass on their knowledge to young generations. Their stories, which Harrison tells with empathy and respect, help us to grasp the impact of language extinction and the realization that when languages are lost, so are culture, diversity, and heritage.