This book describes several aspects of syntax and semantics of romance languages assuming the point of view of a constraint-based, non-transformational linguistic theory, i.e. Head-driven Phrase Structure Grammar (HPSG). Besides the widening of the empirical coverage of HPSG the theory, its main significance consists in a refinement of the theory itself, on the basis of data from romance languages. It contains essays discussing phenomena from Catalan, French, Italian and Spanish.