The Ph.D. thesis of Roland Schütze examines how fuzzy methods can be used to manage service levels in the alignment of business and IT. It starts by mapping the dependencies of service-level agreements, coming up with gradual and bipolar concepts to eventually classify the coupling level by intuitionistic fuzzy sets. It presents an approach to analyze the impact of service failures using intuitionistic fuzzy methods. Finally, this work extends the concept toward business and IT-aligned, service-level engineering, providing a use case.