This paper propose a progressive and disciplined engineering of adaptive service-oriented business processes (SO-BPs). Each business activity is first informally governed through interaction-centric event-conditions-actions (ECA) based business rules. They are then smoothly conceptualized as transient ECA-driven architectural connectors, with roles playing service interfaces and glues capturing the service composition logic. This ECA-driven architectural conceptualization is formally validated using (still rule-centric) rewriting logic and its MAUDE language. From these founded, certified and adaptive SO-BPs, a compliant .NET based Web-services are systematically derived.