A model of communication that is able to cope simultaneously with the problems of search and congestion is presented. We investigate the communication dynamics in model networks. Those networks consist in a regular lattice ordering plus some long-range short-cuts with a given probability. The destination nodes of the short-cuts are chosen according to some degree of preferentiality. We study then the interplay between short- and long-range links and preferentiality. We also introduce a general framework that enables a search of optimal structures. A relation between dynamical properties and topological properties of the network is found and exploited.