This book examines the structure and function of the English it-cleft configuration from within the framework of construction grammar. It defends a straightforward extraposition-from-NP analysis (on which the cleft clause is a restrictive relative, modifying the initial it) and claims that all types of it-cleft involve nominal predication. Support for this analysis comes from three main areas: (a) the central role of definiteness in the creation of specificational meaning, (b) the existence and makeup of predicational (and proverbial) it-clefts, and (c) the early, historical it-cleft data....