Abstract A multicomponent metal chelate system is set up containing six metal ions of the type commonly found in environmental systems. and five ligands which vary considerably in basicity and metal ion affinity. With the use of critical stability constants. computer calculations iire carried out to show the equilibrium distribution at' metal ions among the various ligands available as the pH is varied from 2.0 to 11.0. Changes in the total concentrations of Ca(1I) are shown to result in considerable changes in the distribution of the remaining metal ions among the available ligands. The methods employed in this investigation are applicable to more extensive and complcx inulticomponent systems containing thousands of ligands and a large number of metal ions.