This book documents the scientific results of the projects related to the Trusted Cloud Program, covering fundamental aspects of trust, security, and quality of service for cloud-based services and applications. These results aim to allow trustworthy IT applications in the cloud by providing a reliable and secure technical and legal framework. In this domain, business models, legislative circumstances, technical possibilities, and realizable security are closely interwoven and thus are addressed jointly. The book is organized in four parts on “Security and Privacy”, “Software Engineering and Software Quality”, “Platforms, Middleware and Integration”, and “Social Aspects, Business Models and Standards”. It thus provides a holistic view on technological, societal, and legal aspects, which are indispensable not only to ensure the security of cloud services and the data they process, but also to gain the trust of society, business, industry, and science in these services. The ultimate goal of the book, as well as of the Trusted Cloud Program in general, is to distribute these results to a broader audience in both academia and industry, and thus to help with the proliferation of "Industry 4.0" services.