Thermodynamic stability diagrams are useful as a way of displaying graphica
lly the thermodynamic stabilities of the various species in a chemical syst
em. The production of these diagrams becomes complicated in a complex syste
m. A general construction method is suggested, which concentrates on the eq
uilibrium lines and uses complete sets of chemical equations determined for
the system. A proof of the method is presented and an example is shown to
illustrate the capabilities of the computerized construction technique.