The long-range goal of the present project is to integrate two important approaches to the study of semantics: the model-theoretic formal semantics tradition with ties to logic and philosophy of language and an emphasis on a compositional syntax-semantics interface, and lexical semantics with its roots in lexically and cognitively based work on semantics and semantic categorization. This project also aims to link Russian and American traditions by building on the Moscow school of lexical semantics. In the study of how lexicon and grammar interact in semantic interpretation, the static view of compositionality as the simple putting together of given lexical meanings into larger wholes has been giving way to a dynamic view in which compositionality is seen in the context of the meaning-shifting potential of the parts that are being combined. Essential issues for the present project include understanding the nature and roles of fine-grained type structure and sort structure of lexical meanings and their effects, in interaction with contextual information, on meaning shifts and coercions. The project's substantive focus is on controversial problems concerning the principles of interpretation of genitives and related constructions with relational and non-relational nouns (John's brother, John's team). These constructions have sparked debates concerning the division of labor and interactions among compositional semantics, lexical semantics, and context.