Flood defences are in practice often multi-used, multi-managed and multi-financed. Flood defence asset management contains technical, organizational and spatial complex issues involving multiple organizations. In the literature, little attention has been given to the conditions for successful cooperation between organizations in flood defence asset management. This paper elaborates on this aspect of mature asset management from a practical point of view. Although the importance of a fit-for-purpose cooperation seems trivial, practice shows that the shape of cooperation is often the coincidental result of implicit or ad-hoc choices and is not deliberately designed. This paper reports on empirical data gathered in a case consisting of five different situations related to collaboration in flood defence management. The management context consists of three main tasks: performance assessment, reinforcement and daily management, and three decision levels: strategic, tactical and operational, resulting in nine different management environments and related interfaces. For effectively achieving desired outcomes, the shape of cooperation has to be explicitly chosen dependent on the complexity of content and organizational context, and relevant external circumstances: situational cooperation.

Flood defences are often situated in public spaces and are mostly multi-functional, multi-financed and multi-managed. Cooperation in flood defence asset management is important because roles and responsibilities are fragmented within and between organisations. This complex context calls for mutual understanding from responsible role-holders. Research has shown that serious games are instrumental to reflect situations in which technical and social complexity both play a role. Serious games motivate participants to learn and to change the way they learn. This paper presents the development, application, and results of a serious game ‘Dike Dilemmas Under Pressure' that aims to create better mutual understanding between actors in flood defence asset management. The game was played with 67 professionals that fulfil a diversity of roles related to flood defence asset management in the Netherlands. The analysis of the results in this paper clearly shows different preferred cooperative attitudes between different groups of role-holders and indicates potential misperceptions. The game participants were enthusiastic about the insights gained. They indicated that it helped them to recognise the broad variety of asset management dilemmas and become aware of their own cooperative attitudes and those of their colleagues towards dealing with these dilemmas. Future application of the game is recommended to monitor the cooperative attitudes of professionals in flood defence and to support the development of teams.