The paper aims to describe the history, state of the art and prospects of the model‘Theory of Functional-Semantic Fields and Categorial Situations’. This framework was introduced by A. Bondarko and elaborated by his students on the basis of his studies in Russian and Slavic aspectology. Modern linguistic sources broadly define functional analysis as a theoretical model opposed to formal (generative or structuralistic) approaches. It may be characterized by several principles including description of typologically different languages, use of quantitative and multidisciplinary methods, and the role of a pragmatic situation of speech. The narrower definition of functionalism is based on the intention to explain linguistic structures and forms by their functions. The history of Saint Petersburg School of Functional Grammar is closely connected with other functional approaches emerging in the 1970’s-1980’s. It started with the publication of several collective volumes prepared by the Group of Functional Analysis headed by A. Bondarko. One of the most important principles of this approach is based on the description of the Russian grammatical system “from semantics to language means of its expression” (opposed to the traditional structuralistic descriptions “from form to its function”). The results are found in the six volumes of The Theory of Functional Grammar [1987-1996]. Further developments of the school are found in the next six volumes of The Problems of Functional Grammar [2000-2017]. They include qualitative studies of L1 acquisition by children, quantitative studies of the National Russian Corpus and a synchronic and diachronic analysis of Russian data compared to a wide range of languages. The model of functional semantic fields and categorial situations becomes a multidisciplinary approach based on valid data which are analyzed quantitatively and qualitatively.