Brown trout are among the fishes most valued by humans for food and recreation. This has not prevented their decline, however, and today native brown trout are found at only a fraction of their historic abundance. Countless native populations have been extirpated by overfishing, habitat destruction, and indiscriminate stocking of hatchery fish; many remaining native populations are in danger of extirpation. If people value brown trout so highly, why have we been unable to stop their precipitous decline? A growing number of scientists and members of the public believe that a reassessment of our valuation of nature is warranted. We believe that a conservation ethic that openly acknowledges nature's intrinsic value is a necessary basis for truly sustainable resource management. In this chapter we briefly outline how Aldo Leopold's well-known Land Ethic, based on an eco-evolutionary worldview, can help us understand our duty to protect native brown trout for their own intrinsic value, in addition to the values they provide for humans.