A multiparameter representativity approach for the design of Advanced full MOX BWR core physics experimental programs in ZPR was developed. The approach is based on sensitivity analysis of integral parameters to nuclear data, and correlations among different integral parameters, largely used for Fast Reactor Applications, in particular by Salvatores et al at the French Atomic and Alternative Energies Commission. The approach was applied to the design of 100%MOX advanced BWR configurations in the so-called BASALA program conducted in the EOLE critical facility, based on PWR MOX fuel pins available in the facility. The adopted scheme proposes an original approach to the problem, going from the initial “microscopic” pin-cells integral parameters to the whole “macroscopic” assembly integral parameters for both “cold” and “hot and voided” BWR situations. The proposed approach, in particular including the representativity extension to power distributions demonstrated the need, not pointed out by a “basic” k-eff analysis”, to provide few more PWR-type MOX fuel pins to achieve a global representativity target value for BWR-types MOX lattices.