A third important task of airport capacity and demand management is to influence or regulate the demand for air travel and services, in order to match it with the available capacity, or to achieve other objectives such as revenue generation, customer satisfaction, or environmental protection. Demand management involves using various tools and techniques, such as pricing, scheduling, slot allocation, incentives, or restrictions, to affect the behavior or preferences of airlines, passengers, or other users of the airport. However, demand management is also a complex and sensitive process, as it requires coordination and cooperation among multiple actors and stakeholders, such as airport authorities, air traffic controllers, airlines, regulators, or customers. For example, imposing a congestion charge or a carbon tax may reduce the demand for air travel, but it may also affect the competitiveness or profitability of the airport or the airlines.