The most high profile transboundary water dispute to ever reach the International Court of Justice – the Gabčíkovo–Nagymaros case – remains unresolved 18 years after the delivery of the judgement. This article suggests that there are at least three structural causes that prevent the parties – Hungary and Slovakia – from coming to an agreement. First is the judgement of the Court itself that has created an ambiguous legal situation that actually helped the parties to reinforce their pre-litigation positions. Second, the Gabčíkovo–Nagymaros dam complex gained an unexpectedly powerful symbolic value in both countries whose antagonistic nature still holds a strong grip on the two governments. Finally, these circumstances have given rise to a negotiating dynamic that is characterised by mutual distrust and dominated by the fear of loss. Consequently, while both countries are aware of what the final outcome should and could be, they are unable to get there as the lack of consensus on the starting conditions of the negotiations and the domestic political domain leaves almost no space for rational concessions. The Gabčíkovo–Nagymaros case is therefore likely to remain unresolved, unless the parties manage to find a new positive negotiating paradigm that subsumes the old rivalry of the underlying dam dispute.