Reform of the secondary school and restructuring of the high school put into the foreground personality of the teacher. The concept of multidimensional development of personality proceeds from L. S. Vygotsky's, S. L. Rubinstein's and A. N. Leontiev's ideas and includes five invariants: spatial-temporal orientation, need-volitional experience, content, level of acquisition, and form of realization of behavior. The concept constitutes the core of an experimental objective research program "Teacher: school - high school - school" suggested by the author; main principles on which the program is based are given.