This text reports the more policy-oriented results of the Biodiversity programme of the Royal Swedish Academy of Sciences Beijer Institute. The programme brought economists and ecologists together to consider where the problem in biodiversity loss really lies, what costs it has for society, and how it might best be addressed. The results are different from those reported in other works on the subject. Biodiversity loss matters for all ecosystems - not just the megadiversity tropical forests. And it matters because it compromises the resilience and so the productivity of those systems.

This volume is one of a number of publications to carry the results of the first research programme of the Royal Swedish Academy of Science's Beijer Institute. The Institute was formed in 1991 in order to promote interdisciplinary research between natural and social scientists on the interdependency between economic and ecological systems. In its first research programme, the Biodiversity Programme, the Institute brought together a number of leading economists and ecologists to address the theoretical and policy issues associated with the current high rates of biodiversity loss in such systems - whether the result of direct depletion, the destruction of habitat, or specialisation in agriculture, forestry and fisheries. l This volume reports some of the more policy-oriented work carried out under the programme. The broad aim of the programme is to further our understanding of the causes and consequences of biodiversity loss, and to identify the options for addressing the problem. The results have turned out to be surprising to those who see biodiversity loss primarily in terms of the erosion of the genetic library. In various ways the work carried out under the programme has already begun to alter our perception of where the problem in biodiversity loss lies and what policy options are available to deal with it. Indeed, the programme has provided a powerful set of arguments for reappraising not just the economic and ecological implications of biodiversity loss, but the whole case for development based on specialisation of resource use.