This Master’s Thesis examines and documents challenges related to the flexible interchange of web services within a cross-cloud Service Oriented Computing scenario (SOC).Starting with a theoretical approach, hypotheses are defined and processed to create testing scenarios for a practical examination. Both examinations are used to identify possible challenges. Next, encountered challenges are described, discussed and classified. Lastly, solution approaches to identified challenges are presented. The solution approaches concern related topics, such as service standardization, semantic methods, heuristics, and security/trust mechanisms. Several approaches to different challenges are reviewed in this particular context, to present an overview for future research on the subject.It is remarkable that there will be more service standardization in the future, but to achieve full automation it will be, on the long run, necessary to evolve and adopt more sophisticated solution approaches such as semantic methods or heuristics.This work is embedded into the framework of a research co-operation between the Linnaeus University Växjö and the University of Applied Sciences Karlsruhe. Results however are also applicable to other research scenarios.