Work on the movement of phrasal categories has been a central element of syntactic theorising almost since the earliest work on generative grammar. However, work on the movement of lexical elements, heads, has flourished only in recent years, stimulated originally by Chomsky's Empty Category Principle, and later by the work of Travis, Baker and Pollock. Parallel to these theoretical concerns, much attention has been focused on the description of verb-second languages and on the movement operations which place the verb in its 'second' position. This volume represents the latest work in an important field, from some of its leading researchers, and puts forward many ideas about relevant principles and parameters of Universal Grammar. It will have a significant impact on its field.