Zscaler Threat Hunting is a managed threat hunting service that provides 24/7 expert-led threat detection and analysis. The service leverages data from Zscaler's secure web gateway, which processes over 400 billion transactions daily, to identify sophisticated threats and anomalies that evade traditional security tools. The service combines human expertise with machine learning models and threat intelligence to proactively hunt for advanced persistent threats (APTs), emerging threats, and malicious activity. Threat hunters analyze web traffic rather than endpoint data to detect and disrupt attacks earlier in the attack chain, before they reach endpoints. The methodology includes collecting and correlating telemetry across Zscaler's global install base, refining data with AI and threat intelligence, conducting structured and unstructured hunting operations, and escalating actionable alerts to customer SOC and incident response teams. The service uses zero trust principles, hypothesis testing, custom playbooks, and combines AI with human expertise. Zscaler Threat Hunting Advanced tier offers personalized onboarding, strategic briefings, tactical reports, and ongoing support. The service aims to reduce alert fatigue by distilling billions of raw transactions into context-rich alerts and actionable insights for security operations teams.