Reference models capture best-practice solutions for a specific industry such as retail, banking, or insurance. The models usually cover the whole range of solution components such as product models, business rules, data models, and service models. Over the past years, business process reference models have gained increasing attention. Process merging is a technique that brings together several process models to create a new process model. In this paper, the authors introduce process merging for a scenario which focuses on the improvement of an existing AS-IS business process by using a reference process model.