The indigenous people of Sabah have a rich oral tradition on knowledge systems related to all aspects of community life. Adat (custom) passed on from generation to generation provides guidelines for peaceful and harmonious coexistence between members of a community and their environment. The principles and concepts behind the traditional knowledge systems can contribute to present socio-cultural and economic-political systems in maintaining the well-being of humanity and conservation of the natural environment. This book is a first attempt to document what is known of Sabah’s indigenous peoples traditional systems. The book is primarily based on reports of community workshops organized by PACOS for five years from 1997.The book starts with a brief description of Sabah followed by the different indigenous systems. Specifically with reference to resource management, it is localized, holistic and integrated in nature. With respect to fish, when their number is on the decline, a communal understanding can be proclaimed by marking a no-take zone for a certain period of time.