Techniques for dynamic service invocation and dynamic service adaptation in the context of a service oriented application. In one set of embodiments, a plurality of mediator services are introduced between the application and a plurality of actual services accessed by the application. The plurality of mediator services are configured to expose a common, abstract operation. At application runtime, the application determines, via a rules engine, a selection of a mediator service, and invokes the abstract operation by sending an invocation message to the selected mediator service. The selected mediator service transforms (i.e., adapts) the message into a format appropriate for invoking an actual operation exposed by an actual service associated with the selected mediator service. The selected mediator service then invokes the actual operation by sending the transformed message to the actual service.