A Quality Management System (QMS ISO 9000) is a standard that documents processes in the business operations in a systematic approach.
Quality Management Systems does not aim to assure 'good quality' by the more fit for purpose definition, but rather to ensure that an organisation or product is consistent. This can be considered to have four main components: Quality Planning, Quality Control, Assurance and Quality Improvement. Quality management is focused not only on product service and quality, but also the means to achieve it.
Quality Management therefore uses Quality Assurance and control of processes as well as products to achieve more consistent Quality.