Nitrate and pesticide leaching led to the designation of groundwater protection zones in Denmark. The protective measures in these zones often clash with local interests in agriculture. Scenarios were used to evaluate the development of a groundwater protection zone in a farming area. Stakeholders are accorded strong influence on the scenarios. Scenario inputs comprised land cover, land use and farmers' plans and preferences, as registered in interviews with farmers. Scenarios were evaluated regarding the effect on nitrate leaching, extent of pesticide-free area and farm income. The scenarios proved effective in modelling coupled development in land use/land cover and nitrate leaching and pesticide-free area. Voluntary commitment to schemes, calculated according to stakeholder preferences, reduced nitrate leaching by up to 15%. Scenarios with additional inputs from experts who formulated more comprehensive landscape projects reduced the present loss by up to 30%. In both cases, the pesticide free areas were doubled. In general, the bottom-up approaches had a lesser effect on reducing nitrogen losses than did the top-down approaches.