Increasing competition and decreasing customer loyalty forced retailers to obtain accurate information about customers’ existing and future needs, their profitability, behaviour, and trends in purchasing. Due to the rapid advancement in technology, retailers have easy access to vast amounts of information about their customers. They can collect and manage customer data and understand their behaviour patterns. The main purpose of the Customer Intelligence is to provide insight into customer’s needs, attitudes, and behaviors towards particular retailer, and all elements of its business as well. In such a way, the retailer is able to build deeper and more effective customer relationships and to improve company’s strategic decision. This chapter focuses on different aspects of Customer Intelligence and the growing interest and importance for its implementation in the praxis. Moreover, the chapter is trying to clarify some misunderstandings of the concept. The study conducted among retail companies dealing with ICT equipment and services on the Croatian market pointed out that Customer Intelligence provided retailers with a successful decrease of the rate of customer defection and a increase in revenues generated by customers.