Spoken on Kurima, a miniscule island in the Miyakojima municipality in Okinawa Prefecture, Japan, Kurima-Miyako is a South Ryukyuan topolect, a regional variant of the Miyako language. With most fluent speakers aged 80 or older and the island’s depopulation progressing, the topolect of Kurima faces imminent extinction, a reflection of a common pattern in the Ryukyus, whereupon the vernaculars of small islands and isolated remote areas have been facing multifold minorization for decades on the part of the dominant variety/varieties of the area (Shimoji and Hirara in the case of Kurima), Okinawan, and standard Japanese. Responding to the urgent task of producing a comprehensive description while it still has native speakers, the present volume is the first ever attempt at a systemic presentation of the Kurima topolect in any language. It also uses comparative evidence from Ryukyuan and Mainland Japonic languages to provide new proto-language reconstructions and offer insights into the history of Japonic languages.