Lexicalism is a theory of information associated with words and what exactly a word is. The authors propose a different idea of what can be contained in words. Lexicalism is first and foremost a hypothesis about functional-semantic information and secondly a hypothesis about the formal expression of this information. Grammar rules cannot change the argument structure of words. Any change to the meaning of words must occur in the lexicon. A new lexical theory of complex predicates is proposed in this volume. The authors argue that previous lexicalist accounts within Lexical Functional Grammar and Head-driven Phrase Structure Grammar have abandoned certain crucial aspects of lexicalism in their efforts to account for analytically-expressed predicates, in particular permitting predicate-formation operations to occur within phrase structure. Although the theory is presented in detail primarily for German expressions of these predicates, consideration is given to cross-linguistic application of this theory.