Linguistics / This dissertation examines the complexity of complementation in O’dam, also known as Southeastern Tepehuan (SET), based on a corpus of twenty-seven hours of naturally recorded speech (105 texts). This complexity is due in part to the fact that the same subordinate marker, na, encodes complements, adverbial and relative clauses, and, in some instances, non-embedded clauses. That is, distributional patterns indicate that na is a polyfunctional marker in SET. In addition to using the na marker, SET conveys adverbial and complement clauses through using non-embedded clauses (i.e., juxtaposition), supporting the notion that subordination does not always involve an embedded association (Cristofaro 2003). Crucially, juxtaposition is used as a coordination strategy. Therefore, investigating clause linkage in SET highlights the formal and semantic categories in which SET differentiates embedded clauses. It further suggests that SET has a continuum of features that distinguish these dependent relationships (e.g., aspect, second position clitics, inherent control, an overt subordinate marker, negation, and focus); thus, this research contributes to recent work on the typology of complementation. All embedded clauses in SET can be distinguished by means of a second position clitic and by the morphology attached to the embedded predicate or to the subordinate marker. More specifically, complements and relative clauses require second position clitics, but adverbials only use them if they are marking switch-reference. This behavior is unique, because adverbials use second position clitics as an indicator of thematic continuity for subjects, suggesting that the development of these clitics evolved independently with the function of marking switch reference. Also, ‘when’ clauses do not have a fixed order compared to locative and manner adverbial clauses, because locative and manner adverbial clauses, along with complements and relatives, always follow the main clause. As for the morphology encoded in complement clauses, SET distinguishes between embedded clauses with or without a complementizer, and on the basis of internal aspectual morphology and inherent control. As a result, it is not the form, but the interface of morphosyntactic, semantic and pragmatic information that helps us identify the type of embedded clause we are facing. / text