Cross-organizational business processes gain more and more attention in the scientific community. For modeling these processes, choreographies are an adequate solution to describe the observable behavior for each business participant and the corresponding protocols between them. Nevertheless, current approaches mainly focus on modeling and conformance checking before runtime. In contrast, this contribution concentrates on the runtime validation of choreographies and will thus propose a monitoring infrastructure that supports this validation. We will sketch the requirements for a monitoring infrastructure as well as the solutions in order to meet these requirements. Without such a reliable monitoring framework, a runtime validation framework simply would not be able to correctly validate the interactions.