Civil aviation has been confronted with the problem of matching its capacity to growing demand long term. This has been a particularly important issue at some large European and U.S. airports where increasing operational, economic, and, particularly, environmental constraints have affected expansion and development. The long-term matching of capacity to demand at London Heathrow Airport in England is discussed. This analysis includes predicting airport demand relative to annual number of aircraft movements and number of passengers, designing solutions for providing capacity, and generating scenarios for long-term matching of capacity to demand. The results indicate that until the year 2020 the airport will permanently struggle with congestion both airside and landside.