The objective of this thesis is the optimisation of business processes and the development of business process Key Performance Indicators (KPI) by answering the question, how can prime models for the optimisation of business processes and the development of Key Performance Indicators be established, by covering latest findings of process management and the need of general application. These models contribute to the improvement of process management, by being a guideline for practical application. Furthermore, the thesis provides an overview of different process management approaches and term definitions. In line with this, most recent and essential fundamentals of process management, e.g. process management approaches are explained in detail. To overcome these needs, the models are applied to the process landscape of the Integrated Management System (IMS) of OMV Exploration and Production (E&P), Austria's largest listed oranisation.