The Sustainable and Green Building Materials ecosystem spans three functional layers. Upstream, raw‑material producers and specialty chemical suppliers provide recycled aggregates, bio‑based binders, and low‑embodied‑carbon components. Midstream, manufacturers and technology firms convert these inputs into certified green products, while engineering, procurement, and construction (EPC) firms integrate them into building systems. Downstream, distribution networks, after‑sales service providers, and end‑user segments such as commercial developers, institutional owners, and residential builders procure and apply the solutions. Value is generated through compliance with green building standards, performance‑based certifications, and lifecycle cost savings, and is captured via premium pricing, project financing, and government incentives. The ecosystem also incorporates financing intermediaries that structure green loans and leasing arrangements, aligning cash flow with the longer payback horizons of low‑carbon construction. Moreover, standards organizations harmonize product declarations, enabling cross‑border procurement.