Bringing together the subjects of English compounding and Chomsky's theory of Lexicalism, Heinz Giegerich demonstrates in this new study the impossibility of drawing a line between compounds and phrases, and therefore between the lexicon and the syntax, the two grammatical modules of Lexicalism. Proposing a new model of grammatical modularity, where the lexicon and the syntax overlap 'like slates on a roof', Giegerich examines long-standing and unresolved questions about the difference between English compounds and phrases. With its detailed study of compound words in English and its comprehensive analysis of Lexicalism's theoretical framework, Lexical Structures: Compounding and the Modules of Grammar will be of profound interest for all researchers and students with an interest in English linguistics, and in morphological, syntactic or phonological theory.