For rail operators, the tender process for contracts to run passenger services includes an assessment of their technical and managerial competence through which they have to demonstrate their fitness to operate such services. Once awarded, the Department holds the operators to account for the level of service that they provide customers, as well as a range of other performance measures. For bus operators, the majority of services outside London are run on a commercial basis. The Office of the Traffic Commissioner has the power to take regulatory action against bus operators who do not operate services in accordance with the registered particulars.