The extent to which river processes and morphology are dependent on climate is an old question. When looking at large time scales climatic cyclicity seems to coincide with alternating events in fluvial development. However, the shorter the time scales at which fluvial development is considered, the more it is difficult to find a close correspondence with climate evolution. Ultimately, it appears that the response time of river processes to climatic change may restrict the sensitivity of the fluvial systems to adapt to short climatic oscillations. The impact of climate on fluvial systems is largely transferred to these systems by the climate-determined soil cohesion and peak discharges. The latter factors are especially related to vegetation cover and permafrost conditions. Finally, a number of basin characteristics are discussed that demonstrate that fluvial systems are not completely controlled by climate. © 2002 Published by Elsevier Science Ltd.