Service-oriented architecture (SOA) has the potential to provide solutions for enterprise application integration (EAI) problems. While core service platform technologies exist, methodological approaches that link the business domain with the platform infrastructure − a prerequisite for an EAI solution − are only beginning to mature. We present a framework for integrating service-centric software systems that emphasizes service architecture as the key to the application integration problem and that proposes a service-centric integration architecture layer to coherently bridge the gap between business and platform layers. Domain models act as drivers of the architectural development and integration process. A dedicated and empirically developed service-specific architecture solution, based on an adaptation of the QUASAR Enterprise methodology, utilizes service and architecture identification techniques.