The Mekong River is a very important water course in SE Asia. The source of the river is located in Southern China near the Tibetan Plateau; from here the river flows south east to the South China Sea. The upper reaches leaving the Tibetan plateau of S. China run parallel to the Yangtze (or Chang Jinag) River. These headwaters are interspersed with steep drops and swift rapids. The lower river reaches are wide and meandering ending in a large delta. Outside of the monsoon period the lower river stretches experience reduced flow levels and are more difficult to navigate. The basin as a whole is one of the richest biodiversity areas on our planet, however damming projects and land use changes are threatening the survival of many of these unique species. The river has a natural flood/drought cycle. As well as being a complex hydrological system, about 70 million people rely on the river. In the lower basin 70% of inhabitants are subsistence farmers. The six counties included in its river basin have different levels of development and rely heavily on the river for food, transport, irrigation and power generation. As a result of its importance international agreements have developed for the sustainable management of the river system, of which the Mekong River Commission is a leader.