Although, the first edition had a similar focus, more than five years have passed since its publication and the biological and social circumstances of the lake have drastically changed due to, for example, the further expansion of alien species, the decrease of indigenous species, the progress of integrated watershed management by the Union of the Kansai Government which was established in 2010, the legislation of the Conservation and Restoration Act of Lake Biwa in 2015 and more. The new edition will therefore feature updated and new information on the above and more topics as well as updated and revised data based on the latest research. Inventories of respective taxa, especially those of small animals, are also revised based on the latest studies. Furthermore, this volume covers the characteristics of the biota of this ancient lake, but at the same time, it will also approach it as a ‘culture ancient lake’. Other topics also include water pollution, lakeshore development, the effects of global warming in the past and present, the influence of people, and countermeasures by local and national governments. Moreover, the volume also provides a comprehensive view on the future of Lake Biwa and that of its residents. Miraculously enough, this ancient lake has kept its water quality clear even until today despite the fact of more than 1.4 million people living on its shores. Finally, the book also gives indispensable information to those engaged in improving and conserving water regimes of lakes and other water bodies all over the world and to those interested in the culture and history of Japan.  Lake Biwa is not only one of the rarest ancient lakes of the world, but the people’s involvement with the lake also goes back a long way. This is shown in the diverse culture developed in this area and in the various archaeological finds that date back as early as the Jomon Period, nearly 10.000 years ago. Today Lake Biwa fulfills an important role as a water resource by providing domestic, commercial, industrial, and agricultural water for over 14 million residents living around the Lake Biwa-Yodo River drainage basin.  This updated volume focuses on the geological and biological features of the lake as well as on the long-term interactions between the people and the lake.