Characteristics of monopoly are significant lack of good competition, lack of valid and good substitutes that can be traded in the market, and also barriers in the market. The goal is to maximize monopoly profits. It is important to stress that any change in product prices respond to customers the extent of their purchases, because demand for the product of a monopolist is not perfectly inelastic. To maximize profits the monopolist must first determine its costs and characteristics of market demand. Knowledge of cost and demand characteristics is of great importance for the success of the company and for making timely and complete economic decisions. The main example of the local monopolies of supply services such as telephone networks, gas, water and electricity. But in the long run none of the monopolist is not completely safe from attacks by competitors. Monopolist charges a higher price than marginal cost, and it makes a monopoly very desirable from the standpoint of business owners, but at the same time a very undesirable from the standpoint of consumers because of higher prices. The biggest problem in the monopoly market is that the company produces and sells the quantity of product less than the level that maximizes the total gain, which is associated with a high price determined by the monopoly.