Techniques are disclosed for achieving context-sensitive confidentiality within a federated environment for which content is aggregated in a distributed Web portal (or similar aggregation framework), ensuring that message portions that should be confidential are confidential to all entities in the federated environment except those entities to which the message portions may properly be divulged. The federation may comprise an arbitrary number of autonomous security domains, and these security domains may have independent trust models and authentication services. Using the disclosed techniques, messages can be routed securely within a cross-domain federation (irrespective of routing paths), thereby ensuring that confidential information is not exposed to unintended third parties and that critical information is not tampered with while in transit between security domains. Preferred embodiments leverage Web services techniques and a number of industry standards.