Book excerpt: Threat intelligence is a surprisingly complex topic that goes far beyond the obvious technical challenges of collecting, modelling and sharing technical indicators. Most books in this area focus mainly on technical measures to harden a system based on threat intel data and limit their scope to single organizations only. This book provides a unique angle on the topic of national cyber threat intelligence and security information sharing. It also provides a clear view on ongoing works in research laboratories world-wide in order to address current security concerns at national level. It allows practitioners to learn about upcoming trends, researchers to share current results, and decision makers to prepare for future developments.