Network industries are industries whose activity involves conveying people, products or information from one place to the other via some kind of physical network. They include transport networks, information networks and utility networks. Network industries basically consist of three types of activity: upstream activities involving the production of core products such as equipment and means of transport; infrastructure activities involving the construction, maintenance and operation of the physical network; downstream activities involving the delivery of network services to final consumers. Network industries have specific characteristics from an economic point of view. Three of these are particularly notable, the last one also from a social perspective.