Zero Trust is everywhere — in vendor pitches, compliance checklists, and security strategies. But most organisations treat it as a product to buy rather than a model to implement. This article cuts through the marketing: what Zero Trust actually is (and is not), the six technology pillars mapped to your Microsoft 365 stack, why Conditional Access is the policy engine that connects everything, why MFA alone does not equal Zero Trust, and what the 2026 "All resources" enforcement change means for your tenant. Includes a visual mental model and a practical framework for getting started.