The emergence of networked eBusiness and the wave of service-oriented computing facilities create new challenges for automating inter-enterprise business process management and eContracting. This development leads to strategical benefits for agile enterprises, but also to new challenges on enterprise system architectures and platforms. This paper discusses the techniques of introducing trust-related decisions into eContracting, and their effects. This work enhances the web-Pilarcos project results on B2B interoperability middleware; the architectural model supported comprises of autonomous business services forming looselycoupled, eContract-governed eCommunities.