A research work on the Dictionary of Nikola Vaptsaprov’s poetry has been carried out at St. Petersburg State University for many years. The frequency dictionary, bilingual dictionary itself – volumes 1, 2, 3 (from “A” to „пламък“) are published, the fourth volume of the dictionary is being prepared for printing. The accumulated experience allows us to draw a number of conclusions: 1) author's lexicography, including the bilingual one, is an excellent method of studying the language and style of the writer; 2) researches on individual features of idiostyle allow for enriching knowledge about the general language lexical fund; 3) the bilingual approach gives a number of advantages: while translating lexemes one gets clearer understanding of the meaning – that is very important for comparative studies; 4) the lexicographical seminars of such a type are an excellent school for future philologists