The problem of constructing the syntactic analysis of a natural-language sentence in the form of a dependency tree can be cast as a constraint satisfaction problem on set variables. We have contributed to the design and implementation of a comprehensive development toolkit for dependency grammars in the formalism of Extensible Dependency Grammar (XDG) [1
], applied this toolkit to statistical dependency parsing [2
], and formulated a relational syntax-semantics interface that exploits the relational nature of set constraints to allow for the mutual disambiguation of syntax and semantics [3
].