Cultural Linguistics is a multidisciplinary field of inquiry that pursues to unravel the nexus between language and culture. This nexus is partly encoded in ELT textbooks developed internationally or locally. The aim of this chapter is to outline the development of Cultural Linguistics as a result of the interplay of ethnosemantics, linguistic anthropology, and cognitive linguistics. The chapter describes cultural conceptualization as the core constituent of Cultural Linguistics and cultural schemas, cultural categories, and cultural-conceptual metaphors as the analytical tools of Cultural Linguistics. Main studies on L1 and L2 framed by Cultural Linguistics are reviewed. Next, the chapter explicates the potential contribution of Cultural Linguistics to ELT curriculum development. Aligned with this, main studies conducted on ELT textbooks from a Cultural Linguistics perspective are reviewed. The chapter ends with areas of future research on the interface between Cultural Linguistics and ELT curriculum.