A new procedure for evaluating the sigma phase precipitation tendency of superalloys has been developed. It is called SIGMA-SAFE. Phase diagrams are used to determine the degree of super saturation with respect to precipitation of the sigma phase as a function of temperature and alloy compositions. It is found that this supersaturation number, Δ, distinguishes between 24 superalloys according to their known tendency to precipitate or not to precipitate the sigma phase, except for one superalloy. This capability of predicting the sigma phase precipitation tendency of an arbitrary new superalloy composition is not shared by PHACOMP. It is shown that Δ correlates quantitatively to wt pct sigma precipitated in a specific alloy. SIGMA-SAFE also yields the multicomponent phase diagram applicable to each superalloy. The usefulness of this information in alloy design is illustrated.