Within a problem of control of dynamic plants under uncertainty are considered
both classical methods of the theory of systems with variable structure, and their modern
development in the form of the theory of new types of feedback. The exact structure of feedback
in control variable structure systems is clari¯ed. Existence of two types of feedback is revealed:
one classical feedback by the general regulation error, and another, new type, the coordinate-
to-operational feedback. Thus feedback is responsible for a set of positive dynamical properties
for control variable structure systems. Also the perspective directions of further development
of the theory of new types of feedback are considered. In particular, methods of simultaneous
control by families of dynamic plants are considered are considered.