摘要:When hydrological models are used in support of water management decisions, stakeholdersoften contest these models because they perceive certain aspects to be inadequately addressed. A stronglycontested model may be abandoned completely, even when stakeholders could potentially agree on thevalidity of part of the information it can produce. The development of a new model is costly, and the resultsmay be contested again. We consider how existing hydrological models can be used in a policy process soas to benefit from both hydrological knowledge and the perspectives and local knowledge of stakeholders.We define a code of conduct as a set of "rules of the game" that we base on a case study of developing awater management plan for a Natura 2000 site in the Netherlands. We propose general rules for agendamanagement and information sharing, and more specific rules for model use and option development.These rules structure the interactions among actors, help them to explicitly acknowledge uncertainties, andprevent expertise from being neglected or overlooked. We designed the rules to favor openness, protectionof core stakeholder values, the use of relevant substantive knowledge, and the momentum of the process.We expect that these rules, although developed on the basis of a water-management issue, can also beapplied to support the use of existing computer models in other policy domains. As rules will shape actionsonly when they are constantly affirmed by actors, we expect that the rules will become less useful in an"unruly" social environment where stakeholders constantly challenge the proceedings