In this review we will discuss the potential for increasing production within natural lakes or manmade reservoirs based on the various enhancement concepts. Enhancements are interventions in natural aquatic resources, and combine attributes of aquaculture - intervention in the life cycle of aquatic organisms - and capture fisheries - exploitation of natural resources. Enhancements are estimated to yield about two million metric ton per year, mostly from culture-based fisheries in fresh waters where they account for some 20 percent of capture, or 10 percent of combined capture and culture production.