Quality control vs. quality assurance

Managing quality on your project means that you must first understand the specific quality expectations of your customer and then put a proactive plan in place to meet those expectations. The "proactive plan" contains a number of elements -- the most important of which are the quality control and quality assurance activities that need to be performed.

Quality control and quality assurance are important concepts, yet most project managers have only a vague understanding of the meanings and the differences between these terms. It's actually pretty easy.

Quality Control refers to quality related activities associated with the creation of project deliverables. Quality control is used to verify that deliverables are of acceptable quality and that they are complete and correct. Examples of quality control activities include deliverable peer reviews and the testing process.

Quality Assurance refers to the process used to create the deliverables, and can be performed by a manager, client, or even a third-party reviewer. Examples of quality assurance include process checklists and project audits. If your project gets audited, for instance, an auditor might not be able to tell if the content of a specific deliverable is acceptable (quality control). However, the auditor should be able to tell if the deliverable seems acceptable based on the process used to create it (quality assurance). That's why project auditors can perform a quality assurance review on your project, even if they do not know the specifics of what you are delivering. They don't know your project, but they know what good processes look like.

Here's an example to drive home the point. Let's say a project manager asked the sponsor to approve the Business Requirements Report. If you were the sponsor, how would you validate that the business requirements seemed complete and correct?

One solution would be for you to actually review the document and the business requirements. If you did that, you would be performing a quality control activity, since your actions would be based on validating the deliverable itself.

However, let's say the document was thirty pages long and that you (as the sponsor) did not have the expertise, the time, or the inclination to do a specific content review. In that case, you wouldn't ask to review the document itself. Instead, you would ask the project manager to describe the process used to create the document. Let's say you received the following reply.

Project manager - "I gathered eight of your major users in a facilitated session. After the meeting, I documented the requirements and asked the group for their feedback, modifications, etc. I then took these updated requirements to representatives from the Legal, Finance, Manufacturing and Purchasing groups and they added requirements that were needed to support company standards. We then had a meeting with the four managers in your area that are most impacted by this system. These managers added a few more requirements. I then asked your four managers to sign off on the requirements and you can see their signatures on the last page."

If you were the sponsor, would you now feel comfortable to sign the requirements? If it were me, I would feel pretty comfortable.

That's the difference. Quality control activities are focused on the deliverable itself. Quality assurance activities are focused on the process used to create the deliverable. They are both powerful techniques and both must be performed to ensure that the deliverables meet your customers quality requirements.