To date, Cloud Computing has primarily been subject to research in the area field of Computer Science. We describe the managerial challenges with an emphasis focus on cost accounting, capital budgeting, and auditing when outsourcing internal functions to the cloud. In a cloud environment, activities of the real organization and the virtual organisationorganization are interrelated and not directly observable. Further, the interrelationship between real and virtual components changes quickly. Both, management and auditors are challenged by an increasing complexity and lack in of transparency of in processes outsourced to the cloud. Complexity and non-transparency cause risks in regard to security and compliance requirements. We propose to use Process Mining to handle complexity and non-transparency for to mitigateing the risks. Process Mining facilitates an enhanced understanding of processes through visualization and detailed analysis. Process Mining can be used by auditors to assess the operating effectiveness of internal controls. However, additional event data are necessary in order to apply Process Mining in the general form of Event Mining for auditing cloud computing systems, additional event data are necessary.