Cloud computing is a new concept using old technologies. It has quickly become a vital tool in organizations across all industries as an Internet-scale computing infrastructure. Nevertheless, despite Cloud computing’s increasing relevance and popularity, there is a lack of understanding of the security risks associated with Clouds and optimal approaches for migration into Clouds. This course covers these from a practical angle; specifically, it covers Cloud computing architecture, management services, and security challenges. It also discusses Cloud migration planning and the main requirements to move current Cloud untrusted infrastructure to a trustworthy Internet-scale Cloud critical computing infrastructure.