Biodiversity is neither a marketable good or product, nor a service; it is the living web that connects the tangible and intangible elements of healthy ecosystems, which is the essence of so-called renewable natural capital. The maintenance of biodiversity is therefore not just an ecosystem service among many—it is the sine qua non of ensuring a sustainable future. That is why the maintenance of biodiversity, partly through the augmentation, or restoration, of renewable natural capital, requires the full attention and action of policy-makers, practitioners, and scientists concerned with sustainability. This, in turn, requires a new approach to accounting and valuation of ecological restoration of damaged or degraded ecosystems. Here we seek to clarify the relation of biodiversity maintenance to ecosystem services, and to outline a new approach to the economic valuation of the restoration of renewable natural capital. A key element in this approach to economic valuation is the development and application of negative discount rates. Changing the way we think about the discount rate and, more broadly, the way we calculate costs and benefits related to restoration can contribute much to advance the maintenance of biodiversity.