This book offers a comprehensive synchronic description of the classifiers of Mojeño Trinitario, an Arawak language spoken in lowland Bolivia. It relies on a systematic in-vestigation of a corpus of texts collected by the author in the field, allowing a quantita-tive investigation of the morphosyntactic and discourse environments of classifiers in natural speech. The book starts off by identifying what Mojeño Trinitario classifiers are, and describing some of their formal characteristics. The language features a set of 32 classifiers, which are suffixes, most often of the CV shape. Even though the morpho-syntactic environments in which classifiers occur are also available to full nouns in compounding processes, classifiers can be distinguished from nouns, because they do not have the capacity to head a noun phrase. The book goes on by describing in detail the semantic extension of classifiers, both at the level of each individual classifier as well as at the level of the system as a whole. Most of the Mojeño Trinitario classifiers express physical properties of the referent they classify, especially shape. Then, the morphological distribution of classifiers on different parts of speech is analyzed. They are found on numerals, nouns, adjectives, and verbs. On verbs, they categorize either the subject, the object, or a peripheral participant. The book furthermore examines the functions of Mojeño Trinitario classifiers: qualification, derivation, and discourse func-tions, as well as an emergent applicative function. Finally, some crucial typological as-pects of the system are that (i) the same set of classifiers is used on different types of hosts, (ii) they are generally not obligatory, except on numerals, (iii) there is no unique association between classifiers and nouns or referents. This nominal classification sys-tem is analyzed as a multilocus and multifunctional classifier system, and also happens to be a good representative of Arawak classifier systems.