Prometheus is an opinionated metrics collection and monitoring system that is particularly well suited to accommodate modern workloads like containers and micro-services. To achieve these goals, it radically breaks away from existing systems and follows very different design principles. In this talk, Prometheus founder Julius Volz will explain these design principles and how they apply to dockerized applications. This will provide insight useful to newcomers wanting to start on the right foot in the land of container monitoring, but also to veterans wanting to quickly map their existing knowledge to Prometheus concepts. In particular, a demo will show Prometheus in action together with a Docker Swarm cluster.