Transitions attract attention, as rare periods of major change that can offer hope (or fear) for sustainability. Research has attempted to uncover the dynamics of transitions of socio-ecological systems. Recently scholars started to look at governance and strategies employed by policy entrepreneurs (individuals or organisations) during transitions, characterised by major policy change. So far the emphasis has been on reinforcing a transition and on transition supporters. The influence of opponents on the direction of a transition and opponents’ strategies remain largely unexplored. This paper looks specifically at the role of individuals and the strategies that they -consciously or unconsciously- use in bringing about or opposing policy change. Five strategies are explored: to develop new ideas, to build coalitions to sell ideas, to use windows of opportunity, to play multiple venues and to orchestrate networks. We discuss the importance of each strategy and what individuals are behind it, using empirical evidence of contested transitions in Dutch and Hungarian water management. Our analysis shows the importance of recognition of a new policy idea at an abstract level by responsible civil servants and advocacy of the concept by a credible regional coalition. The recognition of a new idea, political attention following a number of major (near) floods and a new government coalition after national elections, provided a window of opportunity for changing water management. Opponents used similar strategies as the supporters of the transition. Opposition is inherent to policy transitions and engaging with opponents is an important strategy for those aiming to manage change