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.