Zoetermeer in The Netherlands. During peak hours the frequency on some trajectories is about 24 vehicles an hour. Dealing with these high frequencies and offering travelers a high quality product, according to waiting times as well as the probability of getting a seat, the operator designed a three step controlling philosophy. The first step is to prevent deviations to occur: the infrastructure is exclusive right of way as much as possible and at intersections RandstadRail gets priority over the other traffic. RandstadRail stops at every stop and never leaves before the scheduled time. The second step in the philosophy is dealing with deviations by planning extra time in the schedule at stops, trajectories and terminals. Small deviations can be solved in this way. The final step to get vehicles back on schedule is done by the traffic control centre: they have a total overview of all vehicles and they can respond to disturbances like slowing down vehicles nearby a delayed vehicle. Experiencing major disturbances rerouting and shortening of lines is possible. RandstadRail is in operation since 2007. The actual data of the performance is used to analyze the actual effects of the control philosophy. It is shown that due to the applied measures the variability of the driving times is reduced. Punctuality has increased as well. This leads to a higher level of service, creating shorter travel times, a better distribution of passengers over the vehicles.