| Prototyping - | (Software Engineering) the creation of a mock-up of an application |
| Quality - | (Software Engineering) the degree to which a product conforms to both explicit and implicit requirements |
| Quality function deployment (QFD) - | (Software Engineering) a technique that translates the needs of a customer in technical requirements for software by assessing the value of each requirement |
| Quality management - | (Software Engineering) a set of software engineering actions that helps ensure that software is built in a way that achieves high quality |
| Quality metrics - | (Software Engineering) measures of quality |
| Re-engineering - | (Software Engineering) a series of activities that transform legacy systems (with poor maintainability) into software that exhibits high quality |
| Refactoring - | (Software Engineering) changing software in a way that improves its internal structure but does not change it external behavior; often conducted iteratively as design evolves into code. |
| Regression testing - | (Software Engineering) tests that are conducted repeated to ensure that a change has not introduced side effects |
| Reliability - | (Software Engineering) a measure of the degree to which software operates reliably over some period of time |
| Requirements analysis - | (Software Engineering) a modeling activity whose objective is to understand what the customer really wants |