Stream restoration is gradually being introduced in the legislative framework of various states. Examples include the European water framework's commitment to restoring surface water bodies, the adoption of the concept of freedom space in the French legislation, the inclusion in the Swiss legislation of the notion of space reserved for watercourses and of the requirement to restore streams to a state close to their natural state, and the inclusion of river corridors in land use planning in the American states of Vermont and Washington. Although this evolution is generally viewed positively by the scientific community, a concern expressed by some is that it could lead to less flexibility and less room for innovation in a field that is still in development.