The current project is to complete the research necessary for writing a grammar of Pilaga, a Guaykuruan language of Argentina. The Guaykuruan languages represent a significant gap in our current knowledge of languages of the world. At present, no comprehensive grammar exists for any language of this family. Furthermore, linguists have no clear sense of how the Guaykuruan family is genetically related to any other family. A grammar of Pilaga will serve various purposes. One is to document a language about which information is extremely scarce. A reference grammar of Pilaga will address topics of current interest among general linguists, such as grammatical relations, word order, lexicalization patterns and syntactic reanalysis of categories. The grammar will be accompanied by a collection of texts that will capture part of the Pilaga culture, and illustrate the use of the language in various discourse genres, including narrative and conversational discourse. Methods to be employed are a combination of traditional field techniques, i.e., recording, transcribing and translating texts; modern data processing; and the application of some recent methodologies in discourse analysis. The timing is urgent for this project. Pilaga is spoken by 2500 people and is under intense sociolinguistic pressure from Spanish. The language of the youngest generations shows a high level of borrowings and switching between Spanish and Pilaga during particular linguistic exchanges is evident.