This review is devoted to the matrix method of simulating complex formation in solution. The applicability of the method to the interpretation of spectrometric and calorimetric data for systems containing simultaneously a large number of complex forms is shown. The works where this method was used to calculate the internal equilibrium constants and cis/trans isomerization constants were analyzed. Using the matrix simulation method, the cooperativity of ammonia binding by Mg²⁺, Ca²⁺, Zn²⁺, Cd²⁺, and Ni²⁺ ions in aqueous solution was demonstrated. For halide complexes of Pt(II), Pd(II) and Au(III) with a square-planar structure, the difference between the mutual influence of ligands in the cis and trans isomers is shown. The question of verifying the hypothesis about the geometry of the coordination polyhedron of Cu²⁺ compounds formed in the processes of equilibrium stepwise complex formation in mixed solvents is considered.