The work investigates and offers some specific approaches in ESP teaching and assessment at different proficiency levels. The research and experience show that professionally focused lexical codifiers have to become an integral part of teaching-learning process, while complex syntactic structures can be introduced at levels A2-B1 (by CEFR) implementing lexograms, which are also provided in codifiers. Teachers-methodologists with implementation of corpus methodology compile lexical and grammatical codifiers for ESP. Students within their professional competence collect and verify necessary vocabulary for updating and upgrading lexical codifiers. They select authentic texts as per courses they major in. English texts they select should be relevant and requested not only in an English language class, but also (if not primarily) in their major study and research activity (seminars, term papers, final graduation papers, etc.).
Along with instruction methodology, ways of assessment are analyzed and specified. Two assessment schemes are offered, i.e. one for a teacher (vocabulary and grammar range, fluency, etc), the other for a student (report relevance, topic significance, understanding facility, etc.). This approach, on the one hand, enables teachers to assess student’s language competence, on the other motivates students to actively participate in class activities, analyze material and make conclusions. Language instruction and assessment processes make the student act as the expert of professional knowledge. Assessment methodology, where a student plays actually a leading part, is integrated into the learning process. This approach efficiently develops competence and skills that meet professiogram requirements. Students are challenged to be fully involved in the learning process and be responsible for their professional knowledge, as it is they, who provide professional evaluation.
Key words: ESP, lexical codifier, corpus-based approach, knowledge assessment, receptive language skills, productive language skills, lexograms.