Fauna and flora oflakes are an integrative result of regional past history and present environmental factors. In the Lake Kinneret area where Prehistoric Man witnessed the last tectonic readj ustments of the Rift Valley, geological events do not belong only to the remote past but still strongly affect the lacustrine environment. It is therefore necessary to give a detailed picture of the regional background and limnological features of the lake (Parts I and II) before describing its planktic and benthic com­ munities (Parts III and IV) and the Vertebrate fauna of the lake and its surroundings (Part V). The trophic relationships between communities are beyond the scope of a Monograph and have consequently not been studied in detail but only mentioned occasionally. It is intentional that Man and his penetration into the Kinneret area have been treated on a purely zoological basis. It underlines the fact that Man, as any other living organism, is part of the ecosystem and ruled by its laws and that his activities have an automatic feed back on his environment. However, in contrast with other living organisms, Man is able to 'utilize' the lakes and their watersheds for his benefit if, by appropriate management, he minimizes the damaging influence of his activities. This is the main purpose of the research carried out presently on Lake Kinneret and its watershed and briefly described in Part VI.