viii Rail privatisation in the early 1990s separated the operation of rail services into two broad elements. The first consisted of the national fixed rail network, i.e the tracks, signalling, tunnels, bridges, stations and depots. The second was train operations. Passenger and freight train operating companies run trains on the tracks though, in most cases, they do not actually own the trains but lease them instead from one of three rolling stock leasing companies.
ix Responsibility for maintenance and renewal of the rail network lies with Network Rail though most stations are leased to the principal train operating company using them.
x Rail franchises confer the right to run, subject to the ORR's approval of access to the network, passenger services for a specified period on a specified part of the network. Train companies bid for franchises on the basis of the quality of service they intend to offer and the amount of funding they require (subsidy) or the premium they would be prepared to pay to run these services. Passenger service provision generally requires a net subsidy from government. Train operators can generate more revenue through attracting more passengers, raising unregulated fares and other commercial income.