Quality can be observed from the perspective of the producers, consumers and markets as well as from the point of view of everyone interested in the firm. Technological progress, globalization and market development have granted the buyer, i.e. the consumer, a privileged position. The buyer defines what quality is, which makes consumers ever more demanding. Quality means a satisfied buyer, therefore producers should take care that their product and service meet the buyers’ requirements. To achieve this, firms have various available tools and systems for quality management. The present research deals with the topic of quality, ranging from the historical development of quality to the quality management system. The paper discusses the quality costs, the quality control methods, the quality management tools, and the quality management systems. This thesis research also focuses on how much small and middle-sized com-panies in the Istrian region apply and implement the following standards: ISO 9001, ISO14001, ISO 50001 and OHSAS 18001.