A new radionuclide quantification method is proposed on the basis of multiple gamma-ray detection, which is two or higher
fold gamma-ray coincidence method. The coincidence method has so far been used for nuclear structure study. We apply this
method for quantification of radioactive nuclei. The advantage of this method consists of high energy resolution and high
sensitivity. It is successfully applied to nuclear waste analysis, neutron activation analysis and prompt gamma-ray analysis.
The principle of the multiple gamma-ray detection method and future perspectives for an innovative pulsed neutron source and
a new detector system will be presented.