This volume offers a much needed typological perspective on impersonal constructions, which are here viewed broadly as constructions lacking a referential subject. The contributions to this volume deal with all types of impersonality, namely constructions featuring nonagentive subjects, including those with experiential predicates (A-impersonals), presentational constructions with a notional subject deficient in topicality (T-impersonals), and constructions with a notional subject lacking in referential properties (R- impersonals), i.e. both meteo-constructions and man-constructions. The typological discussion benefits from a good coverage of impersonality in European languages, but also includes considerations of several African, American, South-East Asian, Australian, and Oceanic languages. The variation in the cross-linguistic realization of impersonality and the diachronic pathways leading to and from impersonality documented in this volume point to a novel perspective on impersonals as transitional structures or an intermediate stage of a more basic diachronic change be it from transitive to intransitive, or from active to passive, or participant-to event-centered construction.