Release 2 extends ThriveOS from an operational management platform into a complete business operating system, organized around ThriveOps' business value streams rather than technology domains. Release 1 established the operational core — people, projects, tasks, governance, and executive oversight. Release 2 adds five business domains: Commercial Operations (the sales-to-cash cycle), Delivery Operations (consulting and implementation delivery), Learning Operations (the core education business, split into Catalog and Delivery sub-domains), Workforce Operations (talent management), and Platform Services (cross-cutting capabilities that augment all domains without owning business data). The "Engagement" entity is introduced as the primary operational entity connecting commercial, delivery, learning, governance, and project execution. An Engagement represents a consulting or implementation engagement with a Client — it is the connective tissue between a sold contract and the delivered work. The architecture adopts a Tenant → Organization → Business Entity ownership hierarchy to preserve future multi-tenant capability. All new R2 entities include an organization_id FK field. R1 entities remain single-tenant for ThriveOps internal use. True multi-tenancy is deferred to Release 3, but R2 is multi-tenant ready. Platform Services contains cross-cutting capabilities — AI, Search, Notifications, Audit, Reporting, Integrations, Identity, and Automation — that augment all business domains without owning business data. AI is positioned as a cross-cutting platform layer, not an isolated module. The architecture preserves the Release 1 Entity Schema Freeze. No existing entity will be modified. All new capabilities are delivered through new entities that reference R1 entities via foreign keys.