By providing a robust abstraction over core computing resources, Mesos does away with what has been until now the foundation of most monitoring systems: the individual host. With that gone, what should monitoring of applications running on Mesos revolve around? In this talk, Alexis Le-Quoc argues that imperative monitoring of hosts must give way to declarative monitoring, built on tags, tasks and queries. With concrete examples and live monitoring data, he will present a better way to monitor Mesos.