ICNDRWM 2019: 21st International Conference on Nuclear Decommissioning and Radioactive Waste Management (from 11-12 April 2019 in Venice, Italy) aims to bring together leading academic scientists, researchers and research scholars to exchange and share their experiences and research results on all aspects of Nuclear Decommissioning and Radioactive Waste Management. It also provides a premier interdisciplinary platform for researchers, practitioners and educators to present and discuss the most recent innovations, trends, and concerns as well as practical challenges encountered and solutions adopted in the fields of Nuclear Decommissioning and Radioactive Waste Management.