The possibility is considered that sulfide transport can be achieved, in principle, in phases based on BaZrS₃ and MLn₂S₄ (M = Ca, Ba; Ln = La, Y, Tm, Nd, Sm, Pr). The regions of solid solutions based on ternary compounds were determined. The phases were studied systematically using conductometry, the emf method in chemical concentration cells with and without transfer, and potentiostatic chronoamperometry. A possible mechanism is proposed of defect formation in successive doping of ternary sulfides with binary sulfides.