This book provides a new take on the longstanding puzzle of intervention effects in questions whereby specific scopal expressions block the interpretation of wh-elements when they occupy a particular position in the semantic representation.

Its central argument is that intervention effects are not a homogeneous phenomenon with a uniform underlying structure mapped to a single interpretive mechanism. Rather, they have distinct sources—a distinction that, to date, has not been systematically made in the study of intervention. The work distinguishes two types of intervention: one stemming from focus-based interpretation failure and another rooted in topicality constraints. Consequently, it proposes a new typology that clarifies the field and paves the way for future cross-linguistic research.

Semanticists, syntacticians, pragmatics researchers, and experts in logic and the philosophy of language will find this book illuminating.