Cloud computing architectures and outsourcing of business processes into the cloud are potential candidates to increase flexibility on the enterprise side when it comes to service delivery. In this paper, we focus on a specific aspect of cloud computing and outsourcing: The use of concepts from crowdsourcing in business process outsourcing (BPO). More concrete, the question addressed in this paper is, whether crowdsourcing is a feasible approach for supporting BPO. Based on a literature study in the areas of BPO, cloud computing and crowdsourcing, this paper identifies potential factors relevant for decision making in favour or against using crowdsourcing in BPO scenarios. The factors identified are investigated in a case study from BPO, which confirms many of the factors and gives reason to believe that the work contributes to a better understanding of outsourcing decisions in BPO and the relevant factors. However, just one case study will not give a conclusive picture whether the identified factors can be assumed to be relevant for the majority of BPO cases.