Abstract: The recent progress of research and development on NDA in safeguarding nuclear materials is described in this paper, including the general information about international cooperation in technique developments and some important research topics as follows: (1) plutonium isotopic measurements by gamma-ray spectrometry; (2) plutonium concentration measurements for solution samples; (3) hybrid K-edge densitometer/XRF. (4) spent fuel verification techniques; (5) segmented gamma-scanner; (6) passive neutron coincident counting for plutonium measurements; (7) neutron interrogation methods.