A rather new and interesting research field in mobile robotics investigates the cooperation of several units and, in particular, the possibility of obtaining a collaborative behavior by decentralized algorithms. Indeed, decentralized algorithms show definite advantages over centralized ones. They are naturally resilient to one-point failure (the loss of one unit), can easily reconfigure themselves, and don?t require a leader in the team. Moreover, they can exploit the increase of computing power that can be achieved by parallelizing the activities. At the same time, the number and length of interrobot communications can be kept smaller than those necessary for centralized activities.