Nowadays businesses are becoming more and more aware of the fact that their customers don’t depend on them but instead businesses depend on their customers. Businesses aim to satisfy the needs of their customers and to build long-term relationships with them. B2B markets strive to create a partnership with customers. The objective of this diploma thesis is to determine the care for selected customers based on the analysis of their importance for the business. The thesis consists of 4 chapters. The first chapter describes the significance of customers in an enterprise, segmentation of customer markets, customer marketing analyses, basic principles and rules of customer care. Development of glassmaking industry is also a part of the first chapter. The second chapter determines the primary goal and corresponding secondary goals. The third part consists of the methodology of the diploma thesis and describes the used methods of customer analysis. The last chapter deals with the characteristics of the selected business, application of chosen analyses and subsequent interpretation of results. The final chapter also puts forward suggestions concerning care for the selected customers.