Extended Detection and Response (XDR) is essential for unifying security signals, accelerating investigations, and stopping attacks, before they spread. This book, Ultimate Microsoft XDR for Full Spectrum Cyber Defence shows you how to harness Microsoft’s powerful XDR stack to protect identities, endpoints, cloud workloads, and collaboration platforms. You will progress from mastering the core Defender products and Entra ID security features to unlocking Microsoft Sentinel’s SIEM and SOAR capabilities. Along the way, you will also build high-fidelity detections with KQL, automate responses with playbooks, and apply Zero Trust principles to secure modern, hybrid environments. Each chapter combines real-world scenarios with step-by-step guidance, so that you can confidently operationalize Microsoft XDR in your own organization. Hence, whether you are a security analyst, architect, SOC leader, or MSSP team, this guide equips you to design, deploy, and scale a unified detection and response strategy—reducing complexity, improving visibility, and neutralizing threats at machine speed. Thus, build a security operation that is proactive, resilient, and Microsoft-native.