Ports require the performance of a number of tasks related to market conditions, the tariffs applied, and the rules governing sub-concessions to providers of services. Public authorities (national, port level) might have a major or minor role in setting various tariffs applying at the port (e.g. infrastructure, service charges). Depending on the governance model, private service providers may require approval or can set the tariffs independently. Governance tasks also include market monitoring, quality of the offered services, the application of competition rules, the undertaking of competition-related investigations, handling and complaints, and arbitration. All these functions, and thus the choices regarding their governance, are interdependent with the other types of port governance tasks.