Introduction For centuries, humanity has exploited Earth’s natural resources, and, for the most part, has been aware of the ensuing global impacts such as climate change, biodiversity loss, disrupted ecosystems, land degradation, and public health emergencies, including novel pandemics. These results in massive economic losses, reduced nature benefits, the loss of natural beauty, and risks to people’s health and well-being. Despite this awareness, the global community has often overlooked scientific guidance and undervalued the importance of nature. Policy formulation and decision-making processes must align with sustainable, safe, and resilient resource allocation mechanisms. It is critical for policy makers to recognize the natural environment and ecosystems as valuable cultural and capital assets, alongside physical, human, social, and intellectual capital. This article is the first installment of the "valuing nature" explainer series. What are the values of nature? Nature and ecosystems provide various goods and services categorized into four main types: (i) provision services (e.g., food, timber, fresh water, medicinal plants); (ii) regulating services (e.g., pollination, purification, climate regulation, flood protection); (iii) cultural services (e.g., recreation, spiritual and aesthetic, education); and (iv) supporting services (e.g., soil formation, nutrient cycling). Based on these services, the values of nature can be classified into use and non-use values. Use values can be direct or indirect. Direct use values are provided by provisional services such as foods, crops, fish, and water directly consumed by people. These values are often priced in markets. Indirect use values are mostly attributed to regulating and supporting services. These values may not be experienced immediately by people but provide functions without which human life and society cannot sustain. In addition to use values, natural systems also generate non-use values, mostly derived from cultural services, categorized into bequest value and existence value. Bequest value refers to the knowledge that future generations can benefit from natural systems, while existence value is related to the knowledge that ecosystems and biodiversity exist. These non-use values are more abstract and rely on human perspective. For example, a person does not need to use or see an ecosystem (e.g., wetland, lake), but its existence may still bring satisfaction and contribute to the person’s welfare. Why didn't society value nature before, and why is it critical to do so now? Until a few centuries ago, humans enjoyed and harvested abundant natural resources without witnessing any major repercussions of their activities. At the time, the demand for and use of nature had not exceeded its capacity for regeneration. Moreover, the loss of habitats or ecosystems could take a lifetime to become noticeable due to time lags, contributing to ignorance of natural assets. For many centuries, it was mistakenly believed that nature could never be irreversibly degraded. The rapid growth of the global population in a limited environment has transformed natural resources from plentiful to scarce. In times of abundance, the marginal values of these resources are minimal. Adam Smith's well-known diamond-water paradox highlights how people historically undervalued water compared to diamonds. Now, however, in an era where water is increasingly scarce, it's crucial to reevaluate this perspective. The marginal value of water is likely to soar as its availability diminishes. When society harms nature to the point where it can't support basic human needs or regenerate itself, the marginal value of nature, or the cost of losing even a single unit of it, could become immeasurable. Valuing nature is challenging due to the complexity of assigning monetary values. While direct use values of ecosystem services have clear market prices, many goods and services from nature lack market value. Various methods, ranging from simple to complex, exist to quantify these non-market values of ecosystem services. It's essential to include all use and non-use values in the total valuation of nature, encompassing non-market aspects such as life support functions, spiritual, emotional, and cultural values. The failure to accurately value nature has exposed the planet to extreme risks, evidenced by the increasing frequency of climate-related disasters, shifts in agricultural productivity due to weather changes, and pandemics such as COVID-19. Previous notions like “nature is priceless” or “you can’t put a price on nature” once considered respectful, now inadvertently contribute to environmental degradation. Without proper valuation, natural assets’ scarcity remains economically invisible, leading to their exploitation for short-term gains and economic growth. This approach results in actions like forest destruction for industrial crops, disregarding forests’ protective role against soil erosion, landslides, and floods. Similarly, water mismanagement—through canalization, pollution, extraction, and rerouting—has resulted in dead fish, dying vegetation, undrinkable water, and the collapse of entire ecosystems. Despite the dependence of many economic activities on natural resources, sustainable utilization remains uncommon due to frequent oversight of nature's value in policymaking. For example, in Western Australia, acknowledging the impact of agricultural water extraction on wetlands and vegetation would require reducing groundwater allocation for agriculture by up to 38%. In New Zealand, Lake Rotorua and its ecosystem services are estimated to be worth as much as $48 million annually. Globally, natural assets are believed to contribute benefits worth at least $125 trillion every year. Emphasizing these figures in policy formulation could lead to improved environmental outcomes. How to reconcile agriculture and industry that have relied on natural resources beyond sustainable and safe limits? Programs like REDD+ and Payment for Ecosystem Services (PES) use monetary values of ecosystem services, such as carbon sequestration and water purification, to incentivize (re)forestation. Countries like Australia and the USA have implemented biodiversity offset and wetland mitigation banking schemes, enabling private businesses to purchase credits from restoration and conservation projects to offset their economic activities. The values of ecosystem services provided by such projects are crucial for credit verification and quantification. In 2012, the United Nations officially adopted the System of Environmental Economic Accounting (SEEA) to integrate environmental and economic factors into a common framework. Despite some controversial arguments about the method, this framework has been accepted as the standard for natural capital accounts by other international organizations, including the ADB, EU, IMF, OECD, and World Bank. What are the key considerations for adopting nature valuation frameworks? The recent "Make Nature Count" event at COP15 emphasized the urgent need for national frameworks to promote greener, more sustainable decision-making. Ecosystems valuation and SEEA methods have been implemented in 11 EU member countries, with pilot programs underway in developing nations like Brazil, India, Mexico, South Africa, and the People’s Republic of China. However, other countries may require additional support to adopt such frameworks, tailored to their unique local cultures and ecosystems. Valuing nature extends beyond pricing ecosystem services for market trade. It entails recognizing nature’s significance as a cultural, economic, and intrinsic asset. Using monetary values offers policy makers and businesses crucial guidance, emphasizing the prioritization of public health and natural capital over private wealth and physical capital. Furthermore, integrating nature's values into environmental markets and policies can promote more efficient and sustainable natural resource utilization. The second and third articles in this series will introduce various approaches to measuring nature and its global implications. Ask the Experts Lan N. Le Environmental Economist, Agriculture, Food, Nature, and Rural Development Sector Office, Sectors Group, Asian Development Bank Lan Le is an environmental economist working on agricultural, environmental, and natural resources management projects in East Asia countries. Prior to joining ADB, she worked as an agricultural economist at the Alliance Biodiversity International and CIAT (one of the CGIAR centers) and contributed to groundwater management, ecosystems conservation, and climate change adaptation and mitigation projects across multiple countries. She holds a PhD in Agricultural and Environmental Economics from the University of Western Australia. Christian Fischer Knowledge Management Specialist (Consultant) Christian Fischer is a water professional specializing in knowledge and project management, data analysis, and communication. He currently supports the projects of ADB’s Agriculture, Food, Nature, and Rural Development Sector Office Sectors Group, where he is involved in research, content creation, knowledge management, and events. He also consults with the World Bank's Water Supply and Sanitation Global Solutions Group and is the co-founder of Onewater, a social enterprise dedicated to building a water-wise world. He holds degrees in Economics and Biology from Munich, Oceanography from Bilbao, and Water Science, Policy, and Management from Oxford. Thomas Panella Director, Agriculture, Food, Nature, and Rural Development Sector Office, Sectors Group, Asian Development Bank Thomas Panella has led water operations in Central, South, and Southeast Asia, directing water and climate change programs in Indonesia, and overseeing operations in Uzbekistan. He joined ADB in 2003 and served as ADB’s chief of the Water Sector Group from 2017 to 2020 and as Afghanistan country director from 2014 to 2017. He holds a PhD and MPP in Public Policy and MSc from the Energy and Resources Group of the University of California, Berkeley. Follow Thomas Panella on Lei Lei Song Director, Economic Analysis and Operational Support Division, Economic Research and Development Impact Department, ADB Lei Lei Song leads a team of economists supporting ADB operations, conducting research on development issues in Asia and the Pacific, and performing analytical work on project economic analysis and impact evaluation. Asian Development Bank (ADB) The Asian Development Bank is committed to achieving a prosperous, inclusive, resilient, and sustainable Asia and the Pacific, while sustaining its efforts to eradicate extreme poverty. Established in 1966, it is owned by 68 members—49 from the region. Its main instruments for helping its developing member countries are policy dialogue, loans, equity investments, guarantees, grants, and technical assistance. Follow Asian Development Bank (ADB) on Leave your question or comment in the section below: View the discussion thread.