Organizations building highly complex business and technical systems need to architect families of systems and implement these with large-scale component reuse. Without carefully architecting the systems, components, organizations and processes for reuse, object reuse will not succeed. Experience with software reuse practice and adoption experience at HP and Ericsson led us to a systematic approach to component-based software engineering, based on object-oriented business and system modeling. This article explains how higher-level UML constructs support architected reuse, and describes a systematic process, leading from the business processes of an enterprise, through the system architecture for a family of applications that support these business processes, to the design and use of highly reusable component systems.