Mathematical models describing the competition in the mass sales market are considered. It is noted that, unlike the classic Cournot, Bertrand and Stakelberg models, price management is not enough for demand management. The number of clients depends not only on the activity of promoting goods and / or services, but also on taking into account the individual needs of each client – a factor in customer focus. The advantages of distributing goods and / or services through intermediary companies are shown.
It also considers a mathematical model that takes into account customer loyalty and shows that market share depends not only on the activity of promoting goods and / or services, but also on the relationship of the supplier with the customer. A mathematical model is proposed, taking into account the presence of intermediaries with competing companies, the dynamics of changes in the number of customers is described by a system of differential equations. It is shown in what proportion market shares are divided for different ratios of coefficients of differential equations.