In this thesis I have studied the strategy dynamics of the Dutch private nature con-servation movement in relation to the agricultural landscape and agriculture. These dynamics maybe best described as a spiral-like development, which is the result of both continuity and development as oscillations in strategy. From 1932 till 1972 four oscillations can be seen: between a broad and narrow view on nature, between a high and a low appreciation of the agricultural landscape, between more and less attention for agriculture and between a construction and a critical position to agriculture. These oscillations cannot be explained by the agricultural development. The strategy of the agricultural organisations contained potentials for co-operation, in the field of nature, landscape and environment. The strategy shifted from land reclamation of wastelands to the care for the agricultural landscape. Especially the environment became an important problem for the agricultural organisations. The attitude to these fields is not just negative. They recognised the importance of caring for nature and landscape, although they often resisted against concrete restrictions. Initially environ-mental problems were a threat for agriculture especially and they claimed a restriction of water and air pollution. After some time agriculture became a source of environ-mental problems itself. The potentials for co-operation have only been used partly. The four oscillations have more to do with some fundamental ambivalences in the perspective of the conservation movement: modern man versus nature, nature as a resource versus Arcadia, wild versus pastoral nature, and optimism versus pessimism. At a specific moment conservationists take a specific position in relation to these ambivalences. Gradually the risks and disadvantages of that position become clear and their importance increase. They reconsidere their position and move up to the other side of the ambivalences. Because of these ambivalences more oscillations can be expected. The ...