This paper and the next two parts are aimed at establishing the limiti
ng identity nature of probabilistic and guaranteeing, or game, approac
hes to the problem of control with perturbations. Certain qualitative
considerations are outlined for comparing such approaches. A basic sch
eme is formalized for a two-stage control with planning by incomplete
a priori information on perturbations and subsequent operational corre
ction based on improved current information. The specifics of the guar
anteeing planning approach have been investigated. An illustrative exa
mple, which has been solved analytically, is given, to corroborate the
usefulness of planning with due regard for operational control.