Bilateral monopoly Suppose the one bar in a small town wants to hire a lounge singer to increase the bar's popularity. Because it is the only business demanding this type of labor, it has monopsony power. There is only one good singer in town, so that singer has monopoly power, as well. The following graph depicts the supply and demand for labor in this market, as well as the marginal expense (ME) curve faced by the bar and the marginal revenue (MR) curve faced by the singer.