A NEW METHOD IS PRESENTED FOR EVALUATING THE PERFORMANCE OF GRINDING WHEELS. THE PROCEDURE UTILIZES MEASUREMENTS OF THE GRINDING POWER, GRINDING RATIO, AND SURFACE ROUGHNESS TO ESTIMATE OPTIMAL GRINDING CONDITIONS AND CHARACTERIZE THE PERFORMANCE OF A TEST WHEEL RELATIVE TO A SERIES OF STANDARD WHEELS OF VARIOUS HARDNESS GRADES. TEST WHEEL PERFORMANCE IS CHARACTERIZED IN TERMS OF A NEW PARAMETER CALLED THE GRADE SPREAD. RESULTS ARE PRESENTED FOR SIX PREMIUM ALUMINUM OXIDE WHEELS WHICH SHOW GRADE SPREADS RANGING FROM 3 TO 7 RELATIVE TO A SERIES OF STANDARD MONOCRYSTALLINE ALUMINUM OXIDE WHEELS.