“Value: Counting Ecosystems as Water Infrastructure” offered by the International Union for Conservation of Nature, is a practical guide explaining the most important techniques for the economic valuation of ecosystem services, and how their results are best incorporated in policy and decision-making. The guide explains, step by step, how to generate persuasive arguments for more sustainable and equitable development decisions in water resources management. It shows that investments in nature can be investments that pay back. This guide is offered as part of the the IUCN Water and Nature Initiative (WANI)’s Toolkit series, which aims to support learning on mainstreaming an ecosystems approach in water resource management. The tools are aimed at practitioners, policy-makers and students from NGOs, governments and academia. Also available in Spanish and Chinese.