Quality systems and principles are essential aspects of high quality clinical transfusion laboratory practice. Many frameworks provide the structure for quality systems, some of which are specific to transfusion laboratory practices such as codes of practice and others are more general including ISO9001 and ISO15189. All these systems follow the same core principles incorporating quality assurance activities, quality control and continual quality improvement processes. The application of quality principles may be divided into five categories: processes, people, material, equipment and management. Specifically these categories must encompass laboratory procedures and analysis, storage and transportation of blood products, documentation of all results, selection, validation and maintenance of equipment used in these processes; the design and provision of a suitable working environment, appropriate storage and maintenance of laboratory and other records, internal and external audits and quality control. Personnel involved at any stage of clinical transfusion laboratory practice should be aware of the importance of quality principles, quality systems and quality management and their role. The strict adherence to well designed standard operating procedures and following definitive safety guidelines further enhances quality systems. Together, application of these principles ensures that all products, processes and facilities meet the required standards and specifications. If quality principles are not applied and errors are not addressed, then the consequences can be far reaching.