First published in 1991, this book examines the communicative properties of 'cleft' and 'pseudo-cleft' constructions in contemporary English. The book argues that these properties cannot be ignored in any attempt to provide an adequate grammatical description of the constructions. Furthermore, they provide a source of explanations for the patterns of stylistic variation displayed by clefts and pseudo-clefts. The book reports findings from a corpus-based study of clefts and pseudo-clefts in modern British English.