This dissertation studies interactions in Spanish and Mapudungu, the language of the Mapuche of south central Chile. It pays special attention to the relation that holds between expressions and the situations evoked. Themes prevalent in current cognitive linguistics, such as schematization and metaphor, are brought to bear in the description. The analysis of Spanish dative-reflexive interactions reveals the existence of a "proxemic cryptotype" - and unnoticed grammatical space characterized by the center-periphery logic of proxemic movements and covering a vast lexical mass ranging from domains of motions to emotions. Mapudungu axis-satellite interactions express affections and directionalities between up to four distinct participants in an egocentrically organized scene. A system of dynamic configurations is proposed to account for the elemental relations involved. In both languages, metaphorical processes abound where the basic dimension of topology and dynamics shape areas such as the orientation in the discourse, evaluations of the scene, and the expression of attitudes. Additional comparison suggests that a fundamental difference between the canonical interaction in a standard European language and the Mapudungu counterpart is the dynamic fixation of the former, as opposed to the dynamic flexibility of the latter, and the topological flexibility of the former, as opposed to the topological fixation of the latter. This work also contains an appendix on the Mapuche and their language. (Emilio Rivano Fischer)