Project Management is the art and science of managing projects with emphasis on quality, cost and time. If we take the aspect of quality, this is one of the factors of the triple constraint that govern the art of project management.
Quality is defined as the degree to which the project meets the requirements (PMBOK, 2009). The operative word here is meeting the requirements and hence anything that is done that is not conforming to the requirements is said to be deviating from the norm of quality. In the subsequent paragraphs, I look at the distinction between quality management and the processes of quality control.
Quality management is the practice of drawing up plans that determine the standards that need to apply to the project, determining who would be involved in managing quality and their specific duties, meetings to determine if the project is conforming to the quality specifications laid out in the quality management plan and laying out the metrics that are used to measure quality. As defined by the PMBOK, Project Quality Management is the comprehensive plan that includes all the components of the quality planning process (PMBOK, 2009).
Quality control, on the other hand, is the set of processes that measure the metrics of quality by assessing the specific project results against standards. Quality control processes are done during project monitoring and controlling functions whereas quality management is done during the initiating and planning phase (PMBOK, 2009). Hence, quality control is the subset of quality management and is the final phase of the project management cycle.
Quality management is all encompassing and consist of laying down standards against which the project quality metrics are defined and need to be measured against. Quality management takes into account the lower level details of how the output of the project is to be tracked and measured. Quality control is the process of ensuring that the quality metrics are met. Hence, while quality management is the process of planning and managing the requirements of the project from the perspective of quality, quality control is the process of measuring the level of output and the quality of the output and typically consists of measuring the output against the quality metrics that were decided upon in the quality management plan.
The reason that quality management and quality control are used interchangeably is due to the perception that quality control encompasses the planning aspect as well. This is certainly true in organizations that do not have a separate quality department and quality planning and quality control is the domain of the project management processes. In organizations that have separate quality departments and where there is a well thought out quality plan, quality management and quality control are separate and are handled by different people.
In conclusion, quality management typically produces as its deliverables a comprehensive quality management plan that includes the quality control aspect of it. Quality control in this case is handled by a different set of people who do the tracking and measuring of metrics in a dedicated manner. Typically, the process of quality management includes the representatives from the quality department and the quality control processes are the reverse with the quality department handling the tracking of metrics and reporting to the project management team. Quality control is an independent audit of the quality of deliverables and is necessary for the sign off of the project.