In response to growing concerns over aircraft noise impacts on outdoor recreationalists, the Department of Defense has initiated a collaborative research program with the National Park Service to study this issue. There are three main objectives to this project. The first objective is to assess park and wilderness land usage by outdoor recreationalists and utilization of military training routes and operations areas within park and wilderness boundaries. The second goal is to assess the response of outdoor recreationalists to military overflights. Recent Air Force sponsored research has examined park visitor reactions to military overflights along a short-hike interpretive trail. However, further research is needed to assess whether outdoor recreationalists seeking more remote back-country wilderness experiences are less tolerant of aircraft overflights. The final goal is to recommend, implement, and assess the effectiveness of various mitigation strategies. Promising mitigation strategies include remapping airspace and establishing operational procedures to minimize overflights of specific noise-sensitive park and wilderness areas, scheduling aircraft operations to minimize the temporal congruence of aircraft and outdoor recreationalists within a given area, and informing outdoor recreationalists of potential overflights within a given area while providing alternative recreational areas where aircraft noise is minimal.