One question many people ask us is: “Can you navigate with X mm accuracy?” And of course, the question is understandable, the newer generations of robots are detached from infrastructure such as rails or induction guidance and they navigate increasingly complex environments. Generally they need to interact with other devices in the environment. Even a robotic vacuum cleaner needs to accurately position itself on its dock to charge its battery. However, this does not automatically mean the robot needs to localize itself accurately all the time. But how do we get a robot to do its work reliably, without accurate global positioning?