National policies for long-term management of radioactive waste have for decades been driven by technical experts. The pursuit of these technocratic policies led in many countries to conflict with affected communities. Since the late 1990s, however, there has been a turn to more participatory approaches. This participatory turn reflects widespread acknowledgement in the discourse of policy actors and implementing organisations of the importance of social aspects of radioactive waste management (RWM) and the need to involve citizens and their representatives in the process. This appears to be an important move towards democratisation of this particular field of technological decision-making but, despite these developments, technical aspects are still most often brought into the public arena only after technical experts have defined the 'problem' and decided upon a 'solution'. This maintains a notional divide between the treatment of technical and social aspects of RWM and raises pressing questions about the kind of choice affected communities are given if they are not able to debate fully the technical options. The article aims to contribute to better understanding and addressing this situation by exploring the complex entanglement of the social and the technical in RWM policy and practice, analysing the contingent configurations that emerge as sociotechnical combinations. Drawing upon empirical examples from four countries that have taken the participatory turn - Belgium, Slovenia, Sweden and the United Kingdom - the article describes the different ways in which sociotechnical combinations have been constructed, and discusses their implications for future practice.