Psychic development in cultural-historical theory of activity

Activity-based model of psychic development is critically analyzed and the means to solve its problems are offered. The author's point of view is that in cultural-historical theory of activity and in based on the latter devel oping education theory there is dual notion of human being as of individuum and as of personality. Another problem is insufficiently strict separation of <<activity>> and <<behavior>> notions and inadequate studing of <<activ ity subject>> notion. The author considers the way of person's understandin g oneself in activity to be a moving power of development. Periodisation of psychic development existing in activity theory is analyzed. The author ar gues that qualitative change of activity system is to be periodisation crit erion.