As a cutting-edge approach to meaning studies in corpus linguistics, local grammar still requires systematic clarification regarding its theories, categories and research methodology. Grounded in Firthian and Sinclairian academic traditions, this study proposes the following core argument: local grammar aims to reconstruct a paradigm for meaning analysis rather than make amendments to traditional grammars. Local grammar specifically defines a shift from the pursuit of universal principles to the description of local patterns, from form-driven approaches to meaning, and function-driven perspectives, and from static prescriptive system to a use-based dynamic descriptive system. Based on those arguements and the previous related research, the paper proposes a three-tier local grammar analytic framework, aiming to systematically reveal how meaning is constructed and realized at different linguistic levels. The first tier, the local grammar of compound lexical items, seeks to characterize the structured patterns of meaning in lexical combinations; the second tier, the local grammar of speech acts, aims to analyze the functional realization of meaning in contexts of specific communicative intentions; the third tier, the local grammar of discourse, is designed to describe the macro-constructive mechanisms of meaning in textual organization. It is indicated that while the three kinds of local grammars vary in their orientations, they share a methodological core grounded in language data in actual use, focusing on the systematic co-selection of form and meaning in specific contexts. This paper aims to provide a clear conceptual framework and methodological reference for local grammar studies, thereby advancing the field from fragmented case analyses toward systematic theoretical construction.