This collection of recent work in Head-Driven Phrase Structure Grammar focuses on interfaces between different grammatical components; its fifteen papers explore interface phenomena such as auxiliary contraction in English, analysis of illocutionary force in HPSG, syntactic and semantic aspects of Korean relative clause formation, negation in Welsh, and several others.

"Complex Predicates" examines a number of linguistic phenomena including auxiliary and verb combinations, causative constructions, predicatives, depictive secondary predicates, and particle and verb combinations and uses scrambling and fronting data to determine that all except the depictive secondary predicates should be treated as complex predicates. Muller's analysis of inflection and derivation is compatible with syntactical analysis of particle verbs; as a byproduct, it also solves the particle verb bracketing paradox often discussed in the literature."