Oligopsony (from the greek «oligoi», few, and «opsõnía», purchase) is a market structure form of imperfect competition characterized by the existence of a relative small number of buyers, and many sellers. It is a similar case to oligopoly but were the oligopolistic powers come from the demand side. Monopsonies, a term first coined by Joan Robinson in her book “The Economics of Imperfect Competition”, 1933, are a particular case of oligopsonies, where there is only one buyer, which holds all the negotiating power.
