This article examines the impact of customer service quality on business success in contemporary competitive markets. Customer service quality is analyzed as a multidimensional managerial factor that influences customer satisfaction, loyalty, repeat purchasing, brand reputation, employee performance, profitability and long-term competitiveness. The article argues that business success cannot be explained only by price, product characteristics or advertising; it also depends on how customers experience communication, reliability, responsiveness, empathy, problem solving and after-sales support.