This paper compares the inherent notions of justice in four different approaches to flood risk management in Europe. As protection against flood risks becomes increasingly difficult, dilemmas of justice emerge: some benefits from flood protection measures whereas others loose. Decisions on whom to protect differentiate between upstream and downstream or left and right side of a river. This raises a central but barely discussed conflict: what (or rather who) should be protected against inundations? This question deals in essence with justice. Justice concerns questions over fairness in the allocation of resources, capital and wealth across different members of society. There are different and contradicting concepts of justice, which differ in interpretations of fair resource allocation and distributions. 'What's the right thing to protect' is thus a question of concepts of justice. This contribution is not an attempt to answer this fundamental question, but it offers a debate on how different concepts of justice provide different answers. These answers will then be related to flood risk management approaches in England, the Netherlands, Germany, and Austria.