Abstract <p>An approach to designing systems of observation of the state space of a reacting mixture is proposed. The observation system consists of subsystems of self-oscillating oscillators observing the phase subspaces of a system of kinetic equations for the observed groups of substances in the reacting mixture. Geometrically, the approach is based on a scheme for synthesizing limit cycles in the observation phase space. In this approach, the output amplitudes of the observing self-oscillating processes established in the observation system indicate stabilization of the concentrations of the observed reagents within their permissible ranges. Some mathematical aspects of the approach are considered. The results of the article are illustrated by numerical modeling of the dynamics of stabilization of the amount of substance and the associated phase dynamics of the observation system.</p>