This report is the first of a series of papers exploring options to make finance serve nature. The first two sections of this paper present the current problem and the main concepts of ‘natural capital’ and ‘ecosystem services’. The third section discusses the current mechanisms for conservation finance, the funding requirement, and where we stand now. The fourth section looks at other possible approaches, including (i) using natural capital accounting techniques (valuation, accounting, reporting, risk-assessment) to internalise the costs of negative environmental externalities; (ii) reviewing the role of supervisory authorities and central banks; and (iii) the case for promoting mission-oriented financial institutions. It concludes with a look at the positive and negative aspects of using natural capital and ecosystem service concepts and the various approaches they give rise to.