This document describes a number of use cases illustrating security and privacy aspects of 5G networks. Based on similarities in technical, service and/or business-model related aspects, the use cases are grouped into use case clusters covering a wide variety of deployments including, for example, the Internet of Things, Software Defined Networks and virtualization, ultra-reliable and standalone operations. The use cases address security and privacy enhancements of current networks as well as security and privacy functionality needed by new 5G features. Each use case is described in a common format where actors, assumptions and a sequence of steps characterising the use case are presented together with a short analysis of the security challenges and the properties of a security solution. Each use case cluster description is concluded with a “5G Vision” outlining the associated enhancements in security and privacy anticipated in 5G networks and systems. A summary of the 5G visions and conclusions are provided at the end of the document.