The Mekong is a trans-boundary river in Southeast Asia. It is the world's 12th-longest river and the 7th-longest in Asia.

The extreme seasonal variations in flow and the presence of rapids and waterfalls in this river have made navigation difficult. The river is a major trading route linking China’s southwestern province of Yunnan to Laos, Burma (Myanmar) and Thailand to the south, an important trade route between western China and Southeast Asia.

The Mekong basin is one of the richest areas of biodiversity in the world. Only the Amazon boasts a higher level of biodiversity. Biota estimates for the Greater Mekong Subregion include 20,000 plant species, 430 mammals, 1,200 birds, 800 reptiles and amphibians and an estimated 850 fish species.