International cooperation is needed to protect migratory species and their preferred habitats across borders. But we know little of the factors that compel people in different countries to cooperate to protect those habitats and species. And transnational cooperation ultimately relates to conservation efforts also in one’s home country. The focus of this PhD thesis is to disclose the spatial supply of and trade-offs in ecosystem services at a local and national scale in Denmark as well as examining the behavioral factors affecting regional and international support and cooperation for transnational ecosystem services. In this thesis I propose a spatial multi-criteria decision analysis (MCDA) approach as a decision support tool for evaluating land use change at a local level to disclose how decisions can affect multiple ecosystem services. In an empirical case study in a Danish municipality a biophysical and economic baseline mapping of ecosystem services is conducted as basis for sensitivity analyses in changing weights of model criteria. The spatial distribution of land use changes is assessed with the outcome in terms of the welfare economics of ecosystem services. Further, I propose the spatial MCDA approach in a national Danish setting in an analysis of the trade-offs between land rent of agricultural use and selected ecosystem services. The model effectively identifies areas suitable for land use change consideration and is applied to a baseline and four distinct scenarios. These scenarios illustrate how land use change decisions can lead to very different outcomes in the provision of ecosystem services. For migratory species transnational cooperation is needed to secure efficient conservation. Using a choice experiment I examine how the support by Danish households to protect open land habitats at home and in a foreign country area is affected by context and framing of the conservation case. The results suggest that if habitat losses as well as gains are a real risk, support for habitat conservation may be higher than in a context of pure gains. This could become an important feature of future valuation studies. And the results suggest that sharing the conservation challenge with other countries could lead to higher support at home. Finally, in a transnational lab-in-the-field experimental setting in Denmark, Spain, and Ghana I examine how framing and added information in a transnational conservation case affect support and cooperation across borders through donations. The dictator game results suggest that pre-donation information on the necessity of transnational collaboration can increase donation levels. And further, instructions that donation levels would be disclosed to others also could increase donation levels. My results could influence how international conservation organizations develop future fundraising campaigns and increase public support.