A detailed review is given of recent developments, status, and prospects of molluscan aquaculture on the Pacific coast of South America. A brief history of the fishery and cultivation efforts reveals that in Colombia (Pacific coast), Ecuador, and Peru the production of molluscs is entirely based on the natural resources and is chiefly restricted to mussels, scallops ( Chlamys purpurata), and the mangrove cockles of the genus Anadara. Culture activities in these three countries are still in a preliminary experimental stage. In Chile, at least nine species of clams (such as Protothaca thaca, Ameghinomya antiqua, Mulinia spp., and Mesodesma donacium), three species of mussels ( Mytilus chilensis. Choromytilus chorus, and Aulacomya ater), the native oyster Ostrea chilensis, and the Chilean abalone Concholepas concholepas are of great commerical value. Large-scale aquaculture efforts, however, are restricted to M. chilensis, C. chorus, A. ater, and the Chilean oyster. First attempts to intensify the culture of scallops ( C. purpurata) in the north of Chile have had favorable results with respect to future large-scale developments. The introduction and cultivation of Crassostrea gigas is still in an experimental stage. Potential intensification and modernization of culture methods; technical, economic, and sociopolitical problems; and new opportunities and prospects for expansion are analyzed and discussed. The discussion includes an evaluation of the fishery and cultivation products in light of the world market. Enhanced production of underutilized species and enhanced use of underutilized areas for future mariculture installations are analyzed in light of potential new markets. Finally, a detailed list of problem areas is given to form a basis for future research efforts.