The thesis is based on the description of the VOC (Voice of the customer) concept and is consisted of a theoretical and practical part. The theoretical part gives insight into the very concept and basic elements of the concept itself, with emphasis on the advantages of using the VOC concept as a part of a business strategy. The practical part refers to presenting case studies for each chapter of the theoretical part. The complete thesis is divided into six basic chapters, excluding the introduction and the conclusion. The first chapter defines and explains the very concept of VOC analysis, and the second chapter completes it with the presentation of the positive results that organizations, which apply this concept, can achieve. The third chapter gives basic guidelines for the implementation of VOC research, including guidelines for setting goals, selecting a research channel, selecting a sample of respondents and developing a survey mechanism. Thereafter, there is a part of the thesis that gives a detailed description of the way VOC studies can be implemented in business on a continuous basis, without a standard form of a questionnaire. The following chapter describes methods of performing a VOC research through customer service and gives the description of the terms CSAT, CES, and NPC, related to the satisfaction of the customer. The thesis is concluded by presenting research results related to the integration of VOC concept in everyday business practice, provided by the magazine The Economist, and the author's review of the complete concept. The whole thesis focuses on providing the guidelines for the optimization of business processes using VOC researches, so that it can be used as a foundation for those who want to acquire basic knowledge about sophisticated ways to build customer feedback databases using the VOC analysis.