This dissertation is an extended argument for the syntactic structure proposed in (1), referred to as the $VICTR\; Hierarchy$ after the initials of the five functional heads it comprises:

(1) [VolitionP Volition [InitiationP Initiation [ConsecutionP Consecution [TransitionP Transition [ResultP Result [VP ] ] ] ] ] ]

The VICTR Hierarchy is a hierarchy of functional heads corresponding to the part of the clause generally known in the minimalist literature as vP' or the thematic domain'. Nominal arguments are merged in the specifiers of one or more of these heads and receive their thematic interpretations on the basis of their merged positions.

Evidence for a model of thematic roles and syntactic argument structure based in the VICTR Hierarchy is presented for a range of domains, with a focus on $split\; intransitivity$.

Split intransitivity is explored initially in regard to English, with close consideration of a range of split intransitive diagnostics (e.g. $out$-prefixation, the resultative construction); a VICTR account of these patterns is presented. A VICTR account of auxiliary selection patterns in Western European languages is also given.

This is followed by analysis of split intransitive case and agreement systems. A formal account of the case and agreement patterns in these languages based in the VICTR hierarchy is presented, derived in part from the inherent case theory of ergativity (Legate 2002, Aldridge 2004 and others) and drawing on a detailed typology. The dissertation then proceeds to detailed analysis of the semantic basis of split intransitive alignment in two languages, Basque and Georgian. Other split intransitive behaviours in these languages are also considered in VICTR terms.

Throughout, the VICTR approach is compared to other approaches to split intransitivity following Perlmutter's (1978) Unaccusative Hypothesis. The VICTR Hierarchy is also compared to the similar proposal of Ramchand (2008). It is argued that the VICTR Hierarchy accounts more readily than these other approaches for the particular classes of verbs identified by split intransitivity diagnostics in the languages considered, and also for cross-linguistic variation in split intransitive behaviours.

Much support, with some caveats, is also found in the data considered for the applicability of Sorace's (2000) Auxiliary Selection Hierarchy (ASH) to a range of split intransitive phenomena cross-linguistically. Together with acquisitional considerations, the VICTR features are argued to allow for a formalisation of the patterns described by the ASH.