We developed a method of rigorous solution of the Onsager’s flow equations using moments of the interdiffusion-parameter integrands for the determination of average ternary interdiffusion coefficients. The analysis developed by Dayananda and Sohn  is the basis for this refined approach. Average main and cross interdiffusion coefficients are determined over selected regions in the diffusion zone using the diffusion-distance moments of the interdiffusion flux flow equations. Thermodynamic stability of solid solutions in the light of interdiffusion phenomenon is taken as validation criteria to identify accurate and reliable values of the ternary interdiffusion coefficients. Regulations are proposed for successful application of the analysis method to various ternary diffusion couples in Ni- and Fe-based intermetallics.