A considerable number of studies on formative teacher assessment and feedback, learner self- and peer-assessment have been carried out in the field of Language Testing and Assessment (LTA) research over the last two decades. These studies investigated the above mentioned concepts from different perspectives (impact of assessment on learning, attitudes towards assessment, comparison between teacher and learner assessment practices, types and quality of formative teacher feedback), in a number of different contexts (English as second language classrooms, mainstream classrooms, immersion classrooms, i.e. for mainstream classrooms, teaching and learning is done through the medium of a second or additional language) and in a number of different ways (experimental studies, observational studies, surveys, research review studies). This paper systematically reviews most the recent research on formative teacher assessment and feedback, learner self- and peer-assessment, and reveals the gaps which have not yet been addressed by the research.