Various categories of resources are crucial for the survival of humanity, such as energy, materials, water and land. Each of these is the subject of a wide research field, including statistics and database creation, modelling, technology development and assessment, scenario development and forecasts, indicator development, etc. Although these research communities operate independently, the insight grows that the use of these different resources is related, and that these linkages need to be taken into account to assess developments and identify progress on the road to sustainable development. An already well known example is the relation between land and energy, especially related to land-requiring bio-fuels. A transformation towards a bio-based economy may thus lead to unwanted side-effects in the area of food provision. A similar linkage can be expected with the use of water: presently, already 70% of water use is for agriculture; when crop production must be multiplied because of energy crops, the water requirement rises as well. Another important linkage is discovered between energy and minerals: the energy demand due to decreasing ore grades may require energy levels unforeseen in the established energy forecasts. And there are many more of such examples. To go forward on the route of sustainable development, it is essential that such linkages are identified and quantified, and that the approach to sustainability becomes truly interdisciplinary. We will present a number of specific examples of resource linkages and discuss how those linkages may constrain options in ways heretofore unidentified.