Introduction: Piotr Gal'perin and the content of psychology

This is the second special issue of this journal centering on the work of Piotr Iakovlevich Gal'perin (1902-1988). The first issue (1989, Vol. 27, No. 3) contained articles directly related to Gal'perin's theory of learning and instruction. In Soviet psychology his name is especially associated with his attempt to transform the sociohistorical approach to human development into a technology of instruction.
His work, however, was not limited to issues in learning and instruction. He was a versatile thinker and scientist who published articles on such diverse disciplines as physiology, psychopathology, special education, psychotherapy, treatment of functional disorders, and the theory and history of psychology.