All over the world, the authors are surrounded by data. There are large volumes of data, but not enough information. This is a problem that many companies and industries are facing. A solution to this issue could be data mining, also known as “Knowledge discovery in databases”. Many institutions hold large amounts of data, due to their work activity and also due to the rapidly evolution of technology. The main goal of the paper is to illustrate the importance of the optimization methods used in data mining process, as well as the specific predictive models and how they work in this field. Also, the customer relationship management systems have been developed lately, offering new opportunities for a strong profitable relation between a business and clients.