The capability of powder diffraction has greatly increased in X-ray diffraction field since the advent of synchrotron light source, particularly third generation synchrotron source, such as SPring-8. In neutron field, J-PARC is about to start. This means we will have advanced powder diffraction instruments in both X-ray and neutron diffraction fields. The capability of powder diffraction is surely affected by the method used in data analysis. The most common analytical method is Rietveld refinement. Recently, the sophisticated analytical method called MEM/Rietveld, become powerful tool to extract the structural information included in the accurately measured experimental data. In this article, possibilities of powder diffraction utilizing advanced neutron source, i.e. J-PARC and/or advanced neutron and X-ray sources simultaneously, will be described bearing in mind that improvement of the advanced analytical method would occur.
