This volume includes grammatical descriptions of Wai Wai, Warekena, a comparative survey of morphosyntactic features of the Tupi-Guarani languages, and a paper on interclausal reference phenomena in Amahuaca. The four volumes of this handbook are devoted to studies of syntactic, morphological and phonological characteristics of the languages of Amazonia, many of which have never been described fully in the available literature, and most of which are little known to the general linguistic community.