Through the overuse and destruction of ecosystems, we are reducing the number of plant and animal species on our planet in a dramatic fashion. But how can we meaningfully argue for the retention of biological diversity? Which motivational resources could environmental ethics provide for the protection of biodiversity? Are species and ecosystems only of benefit to us humans, or do they possess value in and of themselves? Andreas Hetzel offers answers to these questions, and pleads for an act of respect towards natural diversity, beyond even contingent human interests in individual aspects of biodiversity.