In recent years, many different architectures have been proposed for autonomous robots that have to operate in a dynamic environment. These architectures address the problem of handling real time worlds for which classic paradigms have failed. However, little effort has been made to illustrate how different autonomous robots are supposed to cooperate in such an environment, despite the fact that most applications involving mobile autonomous vehicles require the activity of more than one entity. The paper addresses this particular problem. It presents an architecture for autonomous robots that have to or may collaborate to perform certain tasks. A practical system is also illustrated. It is in the advanced implementation phase, with prototypical vehicles operating in our department area, capable of collaborating and moving fluently even in crowded areas.