In this paper we present an approach to the development of monitoring solutions for processes implemented as WSBPEL service compositions. The approach allows modeling of process performance metrics in a platform-independent manner and then generating an event-based monitor model for a specific WS-BPEL process engine. We create a metamodel which enables modeling of different types of process performance metrics. In particular, our approach supports modeling of metrics related to correlated processes. In the deployment phase, we generate a monitor model based on a proprietary event metamodel of a process engine. In addition, we determine which events are needed for the calculation of PPMs, and generate corresponding deployment information for the process engine.