Liver fluke is a collective name of a polyphyletic group of parasitic trematodes under the phylum Platyhelminthes. They are principally parasites of the liver of various mammals, including humans. Capable of moving along the blood circulation, they can occur also in bile ducts, gallbladder, and liver parenchyma. In these organs, they produce pathological lesions leading to parasitic diseases. They have complex life cycles requiring two or three different hosts, with free-living larval stages in water.

The Integrated Opisthorchiasis Control Program, commonly known as the "Lawa Project", located in Khon Kaen Province, Thailand, is an effort to reduce chronic infection by the Southeast Asian liver fluke among the native peoples of Isan, the northeast region of Thailand. The project operates under the aegis of the Tropical Disease Research Laboratory, Department of Pathology, Faculty of Medicine, Khon Kaen University. It is directed by Banchob Sripa. Its aim is to eliminate the practice of consuming raw or undercooked fish, the major cause of liver fluke infection and bile duct cancer in the region. The project is unique in that it follows the principles of EcoHealth, a One Health approach to improving human and animal health. The project has been the subject of newspaper and TV reports by BBC, The New York Times, and The Guardian.