The contribution deals with material selection strategy in mechanical design. Material selection is tackled in four steps. The first step is translation-reinterpreting the design requirements in terms of function, constraints, objectives, and free variables. The second step is screening-deriving attribute limits from the constraints and applying these to isolate a subset of viable materials. The third step is ranking-ordering the viable candidates by the value of a material index, the criterion of excellence that maximizes or minimizes some measure of performance. The last step is documentation-seeking documentation for the top-ranked candidates.