Today's business climate requires organisations to constantly evolve IT strategies to respond to new opportunities or threats. Tracking the achievement of business goals, objectives and strategies is increasingly used to measure and adjust the outcome of business processes. In this paper, we introduce a web service-based approach for probing WSBPEL processes. With our approach, organisations are able to automatically extend existing WSBPEL processes with auditing extensions which capture audit information during process execution time. We show how to transform a WSBPEL model into an auditable model in order to seamlessly integrate audit trails on different process engines for monitoring purposes. Based on our experience building an auditable process model, we discuss various ways for extending WSBPEL for auditing purposes.