The rapid loss of biodiversity (however measured) constitutes an urgent need to develop policy strategies that reduce the anthropogenic pressures on biodiversity. To go beyond short-term curative measures, such strategies must address the driving forces causing the pressures in an integrated fashion, covering a wide range of policy domains. The development of scenarios and their illustration by modelling are essential tools to study the aggregate human impacts on biodiversity, and to derive well founded policy options to preserve it. However, so far socio-economic, climate and biodiversity models exhibit a wide range of assumptions concerning population development, economic growth and the resulting pressures on biodiversity. This paper summarizes the efforts undertaken in the framework of the ALARM project by an interdisciplinary team of economists, climatologists, land use experts and modellers to identify pressures and drivers, and to derive effective policy strategies. It describes the challenges of such a kind of work, bringing together different world views necessarily inherent to the different fields of investigation, presents preliminary results, indicates necessary policy priorities and suggests urgent issues for future research. Copyright © 2007 John Wiley & Sons, Ltd and ERP Environment.