The service-oriented architecture (SOA) has been successfully applied in enterprise environments. Due to decentralized set-ups, mergers and acquisitions and organizational boundaries, many enterprises today operate multiple, fragmented and heterogeneous service infrastructures that are administered by different organizational units. This fragmented infrastructure causes service duplication and unnecessary redundancy. This paper proposes an approach of cross-domain service integration through an automated federation of Enterprise Service Buses (ESBs). ESBs are the mediation centers within a service domain that enable service interaction across technological boundaries by using service proxies. We present DISCE, a configuration engine prototype that enables an operator to configure service connectivity in such an environment in a declarative form, by specifying simple rules. The engine produces a configuration consisting of a set of proxies interconnecting clients and services. © 2010 IEEE.