This paper discusses the need and possibilities for conservation of riparian ecosystems with emphasis on two important groups of tree species in these flood plain river ecosystems, poplars and willows. It puts conservation and restoration activities into perspective with the needs and benefits for society and the environment. Natural ecosystems of poplar and willow that still exist are relatively scarce and although much is known about the different components that together make up such an ecosystem, relatively little is known about the system itself. The managers of ecosystems have to deal with many influences that come from outside the ecosystem: not only upstream and downstream, but also perpendicular to the river. The influence of mankind, by means of its actions that reflect the opinion that nature is secondary to economics, is identified as one of the major problems.