The Kayapó Indians of Brazil's Amazon Basin are described as effective managers of tropical forest, utilizing an extensive inventory of useful native plants that are concentrated by human activity in special forest areas (resource islands, forest fields, forest openings, tuber gardens, agricultural plots, old fields, and trailsides). Long-term transplanting and selection of plants suggest semi-domestication of many species. The overall management strategies of forest also includes many manipulated animal species (birds, fish, bees, mammals) utilized as food and game. Forest patches (apêtê) are created by Indians from campo/cerrado using planting zones made from termite and ant nests mixed with mulch: formation and development of these is briefly discussed, including the implications for new ideas concerning reforestation and campo management. Finally an integrative cognitive model is presented showing the relationships between variants of forest and savanna recognized by the Kayapó. Indigenous knowledge of subtle similarities between conceptually distinct ecological units in the model allows for the interchange of botanical material between microclimates to increase biological diversity in managed areas. It is suggested that indigenous knowledge is extremely important in developing new strategies for forest and campo/cerrado conservation, while improving productiveness of these ecological systems. Such knowledge is not only applicable for Amazônian Indians, but also has far-reaching implications for human populations throughout the humid tropics.