Workflow forms a key part of many existing Service Oriented applications, involving the integration of services that may be made available at distributed sites. It is possible to distinguish between an "abstract" workflow description outlining which services must be involved in a workflow execution and a "physical" workflow description outlining the particular instances of services that were used in a particular enactment. Provenance information provides a useful way to capture the physical workflow description automatically especially if this information is captured in a standard format. Subsequent analysis on this provenance information may be used to evaluate whether the abstract workflow description has been adhered to, and to enable a user executing a workflow-based application to establish "trust" in the outcome.