Sustainable forest management once meant sustained yield, which, according to the Society of American Foresters' Dictionary of Forestry, is “the amount of wood a forest can continuously produce at a given intensity of management.” During the 1990s the scope of sustainable forest management broadened. Instead of viewing the forest as the source of any one economic product (for example, timber, paper, or mushrooms) or service (for example, recreation), sustainable forest management now recognizes the full range of environmental, social, and economic values of the forest. Its mission is to integrate the management of these values so that none are neglected, ensuring that the forest remains both useful and healthy into the future.