The European Union (EU) aims to be climate-neutral by 2050, becoming an economy with net-zero greenhouse gas emissions. This objective is at the heart of the European Green Deal and in line with the EU’s commitment to global climate action under the Paris Agreement. Through the Taxonomy Regulation Complementary Delegated Act, the Commission has concluded that nuclear energy, subject to strict safety and environmental conditions, can play a role in the transition towards climate neutrality in line with the Green Deal. This is also a practice of some EU Member States. It encourages the development and improvement of safety standards for nuclear technologies, including advanced waste-minimising technologies and new nuclear energy generation projects.\nThis portfolio ensures continuity between short- and long-term research and competences in the context of the energy transition and decarbonisation of the EU economy by 2050, through a number of research activities that contribute to safety optimisation of existing and new nuclear technologies.\nAs part of the JRC work programme 2023-2024, this science for policy report covered the achievements of PF4 and highlighted the JRC research efforts in the field of safety of the nuclear life cycle, radioactive waste management and disposal, radioactivity in the environment, nuclear applications, open access and nuclear data, and knowledge management and foresight.The report does not encompass the entirety of PF4’s project results but rather serves as a noteworthy demonstration of the JRC’s scientific excellence. Special recognition is to be given to dedicated efforts toward the development of the next generation of nuclear scientists and engineers.