This book documents the interrogative system of Ikpana, an endangered indigenous Ghana-Togo Mountain language of eastern Ghana. It encompasses both syntactic and phonological aspects of question formation, and draws on original fieldwork and a combination of formal/theoretical and experimental methodologies. This volume is an excellent example of how bringing together theoretical and descriptive linguistics deepens our understanding of language structures. What's more, it clearly demonstrates how the different components of grammar-phonology, morphology, syntax, semantics-are inextricably linked, and a deep knowledge of each part is crucial for understanding the system as a whole. The diverse team of authors combine their strengths to present a cohesive and detailed description of Ikpana's interrogative system, but in doing so, they also paint a much broader picture of Ikpana and Ghana-Togo Mountain grammar, the phonology-syntax interface, and the importance of language documentation and description for theoretical linguistics.