Three organizations are involved in the preservation of the natural surroundings, landscape and cultural history of the Defence Line of Amsterdam. They manage or own the forts and make them accessible to the public. At the behest of the national government, Staatsbosbeheer manages the forts near Edam and Uithoorn as well as Vuurtoreneiland. Natuurmonumenten is a private national organization that manages seven fortresses in the Beemster Polder and in the southern peat river area. Finally, the provincial organization Landschap Noord-Holland manages four forts along the line Krommeniedijk – Zuidwijkermeer.
Managing nature in and around the Defence Line of Amsterdam is a costly and labour-intensive affair. Because of the small scale and relief of the forts, the work has to be done by hand. In and around many fortresses, volunteers are involved in managing the trees and reeds. These volunteers also collect historical data that are used for guided tours and for the restoration of the forts. Without the help of volunteers it would be impossible to open the forts to the public.