Interventional imaging includes real-time imaging methods that can be used during interventions. Since a good image quality as well as fast acquisition and image processing have to be combined, this means that sophisticated methods have to be used and optimized. In this course chapter we give an overview of the topics in this course and then present the essential mathematical concepts of the singular value decomposition that you need to know about for theoretical and practical reasons (you might know this part from the course MIPDA).