Fonds consists of correspondence, reports, clippings, photographs and hand-drawn maps that document Madsen's involvement in various environmental campaigns in the Okanagan region. Campaigns include: Bodega Head, 1962; Brent Mountain, 1961-92; Spotted Lake, 1978-89; Trout Creek, 1972-93; and Uranium, 1971-95. The fonds also includes several files on the Sierra Club, 1971-83; and the Okanagan Similkameen Parks Society, 1966-69; and 4 chalk drawings of landscapes.