The present paper briefly discusses the history, principies and prospects of biological weed control in Chile. From 1952 to 1990,3 insects and 2 fungi were introduced against the exotic weeds Hypericum perforatum, Rubus spp, Galega officinalis, and Ulex europaeus. AII biotic agents released have become established providing from substantial to partial control of the target weeds. Most of the weeds oceurring in Chile are exotic. Natural enemies, particularly insects, have been used against 25 ofthese weeds in other parts of the world. Providing specificity test to chilean wild flora related to the targeted weed, it is consequently possible to transfer successful biological control agents to the country subtantially reducing the initial expenditure of time, personnel, and money involved in searching the agent and testing it suitability for a new habitat. This fact and the ecological and climatic similarities of Chile and areas of the world where biological control of weeds has been extensively and successfully explored and used in the last 50 years, suggest promising prospects for an expansion of the classical biocontrol of weeds in the country.