The GEO Handbook on Biodiversity Observation Networks Biodiversity observation systems are almost everywhere inadequate to meet local national and international (treaty) obligations. As a result of alarmingly rapid declines in biodiversity in the modern era there is a strong worldwide desire to upgrade our monitoring systems but little clarity on what is actually needed and how it can be assembled from the elements which are already present. This book intends to provide practical guidance to broadly defined biodiversity observation networks at all scales but predominantly the national scale and higher. This is a practical how to book with substantial policy relevance. It will mostly be used by technical specialists with a responsibility for biodiversity monitoring to establish and refine their systems. It is written at a technical level but one that is not discipline bound: it should be intelligible to anyone in the broad field with a tertiary education 1. The Biodiversity Data Impediment to a Sustainable World (Working in a Networked World) 2. Essential Biodiversity Variables 3. Stratification and Terrestrial Ecosystem Observations 4. Ecosystem Services 5. Species Observations 6. Monitoring Changes in Genetic Diversity 7. Marine and Coastal Systems 8. Biodiversity Observations for Freshwater Ecosystems 9. Remote Sensing for Biodiversity 10. Involving Citizen Scientists in Biodiversity Observation 11. Biodiversity Modelling 12. Cyber Architecture 13. Using Data for Decision Making: From Observations To Indicators and Other Policy Tools 14. Capacity Building in Biodiversity Monitoring Case Studies