Dagster's code location architecture organizes data pipelines by grouping assets, jobs, schedules, and sensors into isolated Python modules with their own environments. Key benefits include dependency isolation (different teams can use different library versions), fault tolerance (failures in one location don't cascade), and organizational clarity via unique namespaces. The post walks through creating a Definitions object, configuring workspace.yaml, managing virtual environments per location, and covers practical use cases: multi-team collaboration, environment separation, version testing, and multi-tenancy. Real-world examples cover e-commerce departments, financial services clients, and data consultancy projects.