In a road infrastructure concession, a public authority risk. And the commercial risk is sometimes too great to grants specific rights to a private or semi-public company be carried by the concession company alone. Commercial to construct, overhaul, maintain, and operate risk should be controlled by mechanisms incorporated in infrastructure for a given period. By contract, the public the contract, but control of the commercial risk must not authority charges that company with making the eliminate incentives.investments needed to create the service at its own cost In addition to safeguarding the community's interests, and to operate it at its own risk. The price paid to the the public concession authority must increase citizen company comes from the service's users, the public awareness about concession decisions, to ensure their authority, or both. social acceptability. In 1999, out of roughly 51,000 kilometers of Formulas for determining toll charges differ through European motorways, about 17,000 kilometers ( 33Europe. So do criteria for selecting concession percent) were concessioned-16,400 kilometers by toll companies. In 1999, the main criteria used were these: and 670 kilometers by shadow toll (design, build, * The amount of public subsidy required. finance, and operate arrangements). Of these, 73 percent * The credibility of the financial arrangements. are managed by the public sector and 27 percent by * The project's technical quality. private companies. State-owned companies have been * The operating strategy and price policy. important in European motorway concessions.* The reputation of the concession company (whether Systems vary among countries, for example, in how it has a construction company among its shareholders, they share risks between the concession authority and the for example). concession company. As the motorway network hasThe increasingly frequent use of private funding must grown denser, attributing commercial risk has become be taken into account when defining the training more difficult. Increasingly, public authorities must play required by personnel responsible for monitoring the a greater regulatory role. Already, bad experiences have concessions.