This book considers the behaviour of this peculiar wh-element across many different languages, including Ewe, Trevisan, Italian, Basque, German, Dutch, Cantonese, Mandarin, English and Hebrew. In ten original chapters, the authors explore various aspects of why-questions, such as the way why interacts with V2 constructions in Basque, with a subject clitic in Trevisan or how its morpho-syntactic make-up determines its merge position in Ewe, to mention but a few. Furthermore, a clear-cut distinction is established between high and low reason adverbials which are subsequently examined in why-stripping environments in Dutch.