Ensuring that the present genera- tion’s growth will still permit future genera- tions to meet their needs and grow requires a sufficient stock of natural capital assets— the renewable and nonrenewable natural resources and ecosystems that provide hu- mans with a wide range of goods and ser- vices. A highly respected economist, Helm proposes a consistent framework and eco- nomically efficient approach to protect and enhance these assets so as to achieve sus- tainable growth.