In the current context of globalization and with the increasing need to automate the work, modeling business processes has become essential. Modeling helps not only to understand processes but also to anticipate changes and build a flexible structure. In this chapter the authors adopt from software engineering the concept of reverse-engineering. For organizations with unmodeled BP, reverse-engineering is a way to provide process models ready for improvement or usage in other stages of the business process lifecycle. This chapter proposes a method for business process reverse-engineering fulfilling these requirements. It consists of a multi-view metamodel, covering all perspectives of a process, and a detailed approach to guide the business process modeler. The approach was tested on a web application from the French academic Information Systems.