The concept of tracking ‡uid policies by packetized policies is extended to input queueing switches. It is considered that the speed up of the switch is one. One of the interesting applications of the tracking policy in TDMA satellite Switches is elaborated. For the special case of 2 £ 2 switches it is shown that a tracking non-anticipative policy always exists. It is found that in general non-anticipative policies do not exist for switches with more than 2 input and output ports. For the general case of N £N witches a heuristic tracking policy is provided. The heuristic algorithm is based on two notions, port tracking and critical links. These notions can be employed in the derivation of other heuristic tracking policies as well. Simulation results show the usefulness of the heuristic algorithm and the two basic concepts it relies on.